"Kenyans are struggling to afford something as basic as a meal and school fees. The so-called bottom-up economic model has become bottom-down. In this day and age, how do we as a country lose 53 lives to banditry?" Wanjigi said.
He was referring to the attacks by armed bandits in Laikipia and Baringo counties, which have so far left dozens of people dead and hundreds displaced.
Wanjigi also accused Ruto of sending Kenyan officers to a "war zone" without proper preparation and consultation.
"The government is at the same time busy deploying 1,000 police officers to Haiti for not peacekeeping but war. Since the Prime Minister of Haiti Ariel Henry has visited Kenya in reciprocation, Ruto should visit Haiti and see what the situation really is like before sending our officers there," he said.
Wanjigi further blamed Ruto for the country's woes, saying he was the "status quo" and the "continuity of the same problems he helped create".
He said Ruto was a "cunning leader" who had been using his "cunning talents" to dress up the same "crooked policies" that failed the country.
"Never! Don't forget, he was the author of the same horrible policies in the past regime. He continually breaks the law, as was evident with the unconstitutional housing levy," he said.
Wanjigi urged Kenyans not to lose hope and to join him in the fight for real change.
"Fellow Kenyans, I understand and share in your pain. We have got a lot of challenges in our great country. But equally, we got enormous strengths. We are optimistic people. We beam daily with hope. We are known for our unrelenting fights for change. We have always shown a greater togetherness," he noted.
"We are going to win our economic and financial security future. Don't doubt. We won't throw our hands and give up. We will not quit. I will not quit until real change is achieved in Kenya," he added.
Wanjigi's statement comes after Ruto and Henry witnessed the signing of a security deal between the two countries on Friday, 1 March, at State House, Nairobi.
Ruto said the deal was part of Kenya's commitment to contribute to the success of a multi-national mission to restore peace and stability in Haiti.
"I take this opportunity to reiterate Kenya's commitment to contribute to the success of this multi-national mission. We believe this is a historic duty because peace in Haiti is good for the world as a whole," Ruto said.
Henry thanked Ruto and Kenya for offering to lead the security mission in Haiti, which has been rocked by political turmoil, social unrest and gang violence.
Stay informed. Subscribe to our newsletter
However, the deal has sparked controversy and criticism from some quarters, who have questioned its legality, feasibility and morality.
On Thursday, 2 March, heavy gunfire paralysed Haiti's capital and at least four police officers were slain as a powerful gang leader announced that he would try to capture the country's police chief and government ministers.
The move came during the absence of Henry, who visited Kenya to finalise details for the deployment of a foreign armed force to help Haiti combat gangs.
Gunmen shot at Haiti's main international airport and other targets, including police stations, in a wave of violence that caught many people by surprise.
At least four police officers, including two women, were killed in an attack on a station near the community of Canaan, according to a police union.
The violence forced the airport, businesses, government agencies and schools to close as parents and young children fled through the streets in panic.