Patna, Mar 23 (IANS): After the income tax department seized Rs.4 crore of money from a businessman-turned-Janata Dal-United treasurer Vinay Kumar Sinha Thursday, the opposition demanded a CBI probe.

Rashtriya Janata Dal (RJD) and Lok Janshakti Party (LJP) leaders said the Central Bureau of Investigation should get to the root of the money found stashed in flour bags.

Sinha is considered close to Chief Minister Nitish Kumar.

"We demand a CBI probe as we strongly suspect that the cash belonged to Nitish Kumar," LJP general secretary Raghvendra Singh Kushwaha said.

He said only a CBI probe would clear the involvement of Nitish Kumar.

Kushwaha said Sinha's proximity to Nitish Kumar was well known as the chief minister lived in Sinha's residence before becoming chief minister in November 2005.

RJD leader Ramkirpal Yadav said the seizure again exposed Nitish Kumar's claims of zero tolerance against corruption.

Ajay Kumar, Director (Investigation) of Income Tax, Patna, said his staff raided Sinha's establishments and premises and seized the cash.

"We have also detected investments worth Rs.25-30 crore by Sinha," he said.