This came as he admitted that pending court cases over the ownership of invaded farms were the main challenges that security officers were currently facing.
In the last three weeks, over 500 squatters have invaded private land in Ndabibi and embarked on tilling and planting, sparking anger and concerns from the owners.
In Mai Mahiu, tens of herders last week burnt down the offices of Utheri Wa Lari farm and vandalised property worth millions over land dispute.
While issuing the warning, Hassan said they would move in to determine who had genuine ownership documents around the disputed land.
He added that due to the pending court cases, it was impossible to move in and evict the squatters but was quick to warn that they should follow law and order.
Pending cases
"We are asking the squatters to respect private land and move out as we await court ruling on the other pending cases concerning land ownership," he said.
Addressing the press after holding a crisis meeting in Naivasha, Hassan at the same time issued a warning to government officers to keep off land disputes.
He said that his office was aware of complaints raised by area residents that some government officers were leasing sections of the disputed land, leading to the current impasse.
In the Utheri Wa Lari case where the court issued an eviction order targeting illegal herders on the vast land, the commissioner said that the county security team was studying the matter.
"The county security team is planning on how to enforce the court order, and we are asking parties involved in this issue to respect the rule of law," he said.
Early in the week, farmers from Ndibithi, Mwana Mwireri, Central and Kiribon accused government officers of leasing out former ADC land to a group of powerful individuals despite the land being in dispute.