Mathira MP Rigathi Gachagua was last evening arrested by detectives from the Serious Fraud Unit.
The MP is facing charges of corruption and money laundering after he allegedly failed to explain the source Ksh12 billion that passed through his bank accounts.
He was arrested as he returned home from Nyeri and driven to the DCI headquarters on Kiambu Road for processing ahead of his court date today.
The DCI said that a number of companies belonging to the legislator were awarded tenders by the Mathira Constituency Development Fund (CDF).
According to the DCI, a number of companies that received tenders from the constituency wired money to accounts belonging to the MP.
Asoma Enterprises and Jenne Enterprises, which got tenders worth Ksh150 million from Mathira constituency is said to have wired some of the money they received to entities owned by the lawmaker.
The DCI further said that MP Gachagua's personal assistant, Jahenda Makaa, is a signatory of several companies that got tenders set aside for the youth in Mathira Constituency.
During questioning, Makaa told detectives that she was a hairdresser and also operated an M-Pesa shop before being introduced to the world of tenders.