From a 'pumbafu' driver to abductions master: How Zachary Kariuki rose from Kibaki's driver to head dreaded squad

Zachary Kiago Kariuki retired in 2025 and was appointed two years ago to be in charge of a unit in the DCI. [Courtesy, Standard]

President Mwai Kibaki once called his driver "bure...pumbafu sana". The crowd in attendance went wild with laughter and when the event was broadcast, so did the nation. The moniker pumbafu became an everyday insult, albeit jokingly. What Kenyans did not know was that the object of the insult was one Zachary Kariuki. Kariuki was President Kibaki's driver and had parked the armoured vehicle on grass. Rain was about to fall and because of the weight of the vehicle, Kariuki thought it would be difficult to move it once the ground was soggy. For his wisdom, he became the laughing stock.

Years later, he is the man those who know him say is causing torment among perceived government critics and their families.

In the shadowy underbelly of Kenya's security apparatus, the retired police officer with no formal investigative training has emerged as the unlikely kingpin running one of the country's most controversial police units. Kariuki, a long-time associate of DCI Director Mohammed Amin, is the man at the helm of the Operations Support Unit (OSU), a secretive police formation now facing intense scrutiny over allegations of involvement in the abduction and torture of government critics.

Apart from DCI Amin, his other bosses are Deputy Inspector General of Police Eliud Lagat and Kipchumba Murkomen, who is the country''s head of internal security. Outside the security networks, Kariuki also takes command from State House operatives.

Kariuki is no ordinary officer. While stations across the country go without cars or fuel, he has 17 vehicles assigned to him. Insiders at DCI say his fleet includes 14 new Subarus, one D-Max, a Ford Ranger and a Toyota Double Cab. The source says the many Subarus that were doing rounds during protests belong to his unit.

He has 46 officers under his command whom he chooses from the General Duty officers. He has no deputy but under him are two inspectors, Karanja and Njoroge.

"Under normal circumstances, a commissioner of police is deputised by an SSP, below whom is an SP. For Kariuki's case, he has the two inspectors followed by two senior sergeants. One is called Githinji Itegi. He also has about 10 corporals and 26 constables," our source revealed.

Adding: "Ideally, such a unit reports to the Director of Operations but for Kariuki he consults the DCI boss directly and takes orders from State House operatives."

Such impunity does the unit exude that, however grave their crimes, little investigation is done, or officers arraigned for the misconduct.

"The unit was present during the raid in a church where Gachagua was attacked; has the matter been investigated? What about the ones who raided All Saints Cathedral? Was anyone indicted?" asks an insider.

CS Interior Kipchumba Murkomen and DCI Director Mohammed Amin. [Courtesy, Standard]

In February 2024, the Office of the Director of Public Prosecutions (DPP) formally charged Kariuki with abduction and torture alongside six of his officers; the case has stalled, with no meaningful progress toward prosecution.

The Standard has established that Kariuki, who retired from active police service, has been retained on a contract that runs until August 2027, strategically positioned just before the next General Election. This arrangement has raised eyebrows among security experts and civil society groups who question why a retired officer with no formal DCI training, as he is trained only in driver and VIP protection services, would be given such a prominent role within an elite police unit.

The OSU was formed in late 2022 following the disbandment of the Special Support Unit, whose officers had been accused of abducting two Indian nationals. The new unit was initially established to tackle armed and hardened criminals, a mandate that would soon change dramatically after the 2024 Gen Z protests. According to sources with intimate knowledge of the unit's operations, the transformation was swift and decisive.

Former DCI Directors had their own specialised units. Kinoti had the Security Support Unit, and Ndegwa Muhoro had the Flying Squad. The OSU appears to have been repurposed to serve political ends, with its officers operating with impunity and outside the normal chain of command.

After reviewing evidence in a harrowing torture case, Senior Assistant DPP Tabitha Ouya signed a damning letter that named seven officers from the unit as culpable for torture. At the top of that list was Commissioner of Police Zachary Kariuki.

The ruling stemmed from the June 2023 arrest of businessman Abdulahi Abdille Isaack. According to the victim's statement, officers from OSU arrested him at a Total petrol station in Hurlingham, Nairobi, where he had gone to buy medicine. What followed was days of unimaginable torture that would leave the victim permanently scarred both physically and psychologically.

The victim was beaten, forced into a vehicle, and subjected to severe physical abuse that left him with injuries to his wrists, private parts, left leg, scalp, and eyes. Officers allegedly took his national ID and a total of Sh1.94 million in cash. A Police Medical Examination report classified the degree of injury as grievous harm. The torture, the DPP observed, was intended to force a confession to robbery with violence, a confession that would never come because the victim had committed no crime.

Chief Inspector Alexander Makoma was named alongside Kariuki in the DPP's torture charges, as well as Sergeant Francis Singila, Corporal Ronald Chemosit, Constable Gabriel Kuria and Constable Jeremiah Chumba. The DPP is yet to respond to The Standard's query about the status of the case.

Despite this damning indictment and the DPP's finding that there was sufficient evidence to charge all seven officers, the case has since stalled. Kariuki continues to operate as head of the OSU, and his officers remain in their positions, protected by powerful connections that appear to have rendered the wheels of justice immobile. And the impunity also runs deep within OSU. Early this year, some officers in the unit wrote to the Inspector General complaining about many things, among them unfair deployment, per diem being paid to a few officers, and ethnic profiling. Instead of Kariuki being reprimanded as the head of the unit, 12 OSU officers got transfer letters on March 25. Some left Nairobi for Tetu, Kuresoi, Mwingi, and Endebess.

The OSU has come under renewed scrutiny following the abduction of Alex Kiprotich, an editor with the Standard Media Group. Dashboard camera footage from Kiprotich's vehicle captured the terrifying moment when four men surrounded his car and demanded that he step out. The officer seen wielding a gun and shouting "Utaona maajabu" has been identified as Chemosit.

Human Rights Watch named the OSU in its 35th World Report, linking it to a surge in abductions across the country and calling for urgent reforms to address the unit's pattern of abuse.

Lawyer Willis Otieno, who has represented several victims of alleged abductions, expressed anguish at the images of the young men alleged to have been involved in Kiprotich's abduction.

"I have seen the photos circulating of the young men alleged to have abducted Alex, the Standard editor. This is heartbreaking," Otieno said. "Look at the faces. Young Kenyans. Young people who should be building their lives, raising families, and pursuing their dreams, not being turned into disposable tools for people hiding behind power."

Suba South Member of Parliament Caroli Omondi has accused the Ruto administration of waging a relentless assault on the Kenyan media, describing a systematic campaign to force the media into submission. His accusations paint a picture of a government that has employed every tool at its disposal to silence independent voices and control the narrative.

"The Ruto administration has subjected the Kenyan media to relentless assault, hoping to force the media into submission and silence," Omondi said. "The government has financially starved the media by deliberately refusing to pay for services rendered, violently attacked, abducted, and threatened members of the press, purported to enforce suspect court orders against the media, and compromised the independence of select journalists through financial inducements to muzzle the media."

Senator Dan Maanzo has insisted that the abductors of Alex Kiprotich be brought before the Senate, alongside the Inspector General of Police and the head of the DCI, to explain their involvement in the abduction. The Senator's demand reflects the growing frustration among lawmakers who believe the executive has overstepped its mandate in deploying security agencies against civilians.

"There is no way there can be abductions in this country and the DCI doesn't know," Maanzo declared. "I will demand that they face the Senate for questioning."

Faith Odhiambo, a prominent legal practitioner, condemned the abduction in the strongest terms while expressing relief at Kiprotich's eventual release.

"I condemn in the strongest terms the abduction of Standard Media Group Associate Editor, Alex Kiprotich," Odhiambo said. "While we are relieved that he has since been released, his abduction remains a grave assault on press freedom, human dignity, the rule of law, and every Kenyan's right to live free from fear."

She emphasised that no journalist should be subjected to abduction, intimidation, or violence for carrying out their lawful work, adding that such acts have no place in a constitutional democracy.

At a glance

Zachary Kariuki Kiago is in the news now as the head of a criminal gang that is abducting Kenyans under the command of Amin, Lagat and Murkomen.

In 2013, he was a DCIO in Embu, working under IG Kimaiyo

In 2023, he was unconstitutionally promoted to the rank of Commissioner of Police by Japhet Koome

In 2024, the DPP recommended that he face charges for the abduction and torture of Abdulahi Abdille Isaack, but nothing happened.

In the same year, he was reported as responsible for the abductions of Tanzanian activist Sarungi Tsehai, Billy Mwangi, Kibet Bull, Peter Muteti, and Ronny Kiplangat, GK Malema and others.