Patna:  A Bihar court on Wednesday issued an arrest warrant against Bihar School Examination Board's former chairman Lalkeshwar Prasad Singh, who has been untraceable and on the run since after his name figured in the Class 12 toppers' scam, police said.

A Patna civil court issued the arrest warrant against Singh, who is a key accused in the case and has gone underground after resigning from the board last week.

"Singh is still absconding after his name figured in the Class 12 toppers scam. Now the Special Investigation Team will send its team outside Bihar to arrest him," a police official said.

Meanwhile, police have arrested two persons, including Singh's private secretary, on Wednesday.

Singh resigned from the post last week after his name cropped up in the scam.

Earlier, the Special Investigation Team (SIT) probing into the scam sought an arrest warrant against Singh.

Singh's wife Usha Sinha, former Janata Dal-United legislator of Bihar, is also missing and on the run since her name too figured in the Class 12 toppers scam.

Amit Kumar alias Bachcha Rai, the mastermind behind the Class 12 Board merit list scam in Bihar, was arrested on Saturday after he surrendered before the police.

Both Singh and Rai are wanted by the SIT in the ongoing investigation into the alleged irregularities in the results of the toppers in the Class 12 Arts and Science examinations this year.

According to reports, the SIT has found evidences that suggest Singh's role in the racket. Evidence collected also indicates the board's complicity in the scam.

Last week five accused persons arrested in the case were remanded in 14 days' judicial custody by a local court in Patna.