The assembly has started grilling some county officials on the alleged misappropriation of funds.
The county suspended five officials last week following revelations that funds meant for development were allegedly spent on unintended purposes under their watch.
The assembly's committee siting in Kisumu led by its Chairman James Sabwengi is investigating circumstances under which Sh19 million meant for the Gender department in the 2014-15 budget was allegedly diverted and used for unintended purposes.
"We are trying to ascertain why the department allegedly allowed the huge sum of money to be used in other departments while neglecting the projects it ought to have funded," Mr Sabwengi said.
Following claims of corruption by the Implementation Report, an arm of the assembly, the House was thrown into action to unearth the scandal, which risks derailing service delivery in the region.
"Before we started the proceedings, we visited sites that were adversely mentioned in the report. The work at the sites was not appropriately done," said Sabwengi.
The committee is expected to table its findings in the House for debate and endorsement.
"We will then forward it (report) to Governor John Nyagarama for execution," said Sabwengi adding that the assembly is also investigating the level of competence among county staff members.
The five who have been asked to step aside to pave way for investigations include Gender, Culture and Social Services Executive Peter Omwansa and his Chief Officer Fridah Nyabega.
Others are Roads and Public Works Chief Officer Ernest Mirara and Water and Environment Secretary Andrew Nyabati.
In the past months, the county has been marred with corruption allegations.
In May, the Clerk of the Assembly James Nyaoga and senior officers were suspended over alleged illegal medical cover and Sh147 million owed to creditors.
The suspension was done after MCAs adopted a report by the Legal Committee. The Committee on Justice and Legal Affairs Chaired by Koina Onyancha made an inquiry into the MCAs' medical insurance cover and came up with a raft of recommendations.
The committee had recommended that disciplinary action be taken against the clerk, directors of Finance and Human Resource and the senior accountant.
"This House resolves that disciplinary action be taken against the officers by the duly mandated legal body, which is the Nyamira County Assembly Service Board, with a view to having them dismissed," the committee recommended.
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