Congress president Sonia Gandhi has called the Delhi state ministers to explain their conduct in the Ashok Malhotra case.

Ashok Malhotra, who runs the canteen in the Delhi Assembly, is alleged to be the kingpin of a multi-crore land scam in New Delhi.

It was also alleged that ministers like Ashok Walia and others were trying to topple the Sheila Dikshit government using the controversy. It is said that a group of ministers had been running a clandestine smear campaign against Dikshit, while lobbying Wadia's case as a replacement for her.

They claim Dikshit must resign due to the alleged involvement of her officer on special duty in getting VIP numbers for Malhotra's fleet of cars.

The Central Bureau of Investigation arrested Malhotra from the Zee television studio in Noida and has now taken him to the CBI headquarters in Lodhi Road for questioning. "We have time till tomorrow to produce him in court," a senior officer said.

CBI Director Vijay Shankar said he was not worried about the Malhotra giving the interview to the television network. "I am not worried about what he had to say. We give a chance to everyone and I have no problem with that," Shankar said.

He said the investigation is at a preliminary stage. "I find amusing that the media is very enthusiastic about the investigation. I would like to give assurance that nobody -- however high -- will not be spared," he said.