Anti-corruption detectives stormed the homes of 12 NYS bosses believed to be involved in the Sh791 million scam on Tuesday.
The homes of former Devolution CS Anne Waiguru, PS Peter Mangiti and former NYS director general Nelson Githinji were also raided, said a source.
Sourcesconfirmed that Ms Waiguru locked herself inside her house in Kihingo estate, Kitisuru.
The ongoing raids are aimed at getting to the bottom of the fraud case.
Officials said the detectives had a court order and search warrants to stage the raids on the homes.
Waiguruâ€™s lawyer Ahmedinassir Abdullahi confirmed that some detectives were at her home. â€œI am told some officers are at the home. I am headed there to see what they want,â€ said Ahmedinassir. The officers are said to have arrived at Waiguruâ€™s house at about 6.30 AM.