Bihar School Examination Board ex-chairman Lalkeshwar Prasad Singh, the alleged mastermind of the toppers scam in the Bihar intermediate examination, and his former Janata Dal-United MLA wife Usha Sinha were on Monday arrested from Varanasi, a senior police officer said.

The Economic Offence Unit of the Bihar police will probe the money trail and their assets, the police said on Monday.The state government has set up the EOU as a separate branch to deal with the cases of economic offences.

"Lalkeshwar Singh and his wife Usha Sinha have been arrested from Varanasi", Senior Superintendent of Police of Patna, Manu Maharaj said.

Their arrest by the Special Investigation Team was made following a tip off about their presence in the temple city of neighbouring Uttar Pradesh, the SSP, who is heading the SIT on toppers' merit muddle, said.

He said further details would be provided later on.

Lalkeshwar Singh and his wife Usha Sinha, a co-accused in the toppers scandal, had gone underground after police had acquired an arrest warrant from a Patna court in the irregularities in the Bihar +2 examination.

The SIT was armed with a court order to attach Lalkeswar Singh's property which would have taken place on Monday.

Usha Sinha, a former JD-U MLA from Hilsa and Principal of Ganga Devi college in Patna from which she was removed, is a co-accused in the case where degrees were allegedly awarded to undeserving students in lieu of a hefty sum of money.

The top scorers in the Bihar state board intermediate exams were exposed in media interviews soon after their Class 12 results were announced last month.

Police had on June 11 arrested Baccha Rai, the kingpin of the toppers scandal, from Bhagwanpur police station in Vaishali district. Rai is the secretary-cum principal of controversial Vishun Rai College.

With inputs from M I Khan from Patna.