The minister said in Patna that 2200 tonnes of excess coal and iron ore were detected in goods trains under different zones during country-wide checks which began on Monday.

Defaulters would have to pay three times the actual freight charges as penalty, Yadav said. The organized racket had the blessings of some politicians and railway employees, he alleged. The minister said that he had information that a few top BJP leaders, associated with a company called Samrudha Overseas Pvt Ltd, were allegedly involved in the racket.

Refusing to disclose the names of the BJP leaders, Yadav said many of them were former ministers. He has sought more details and said he would soon unmask them.

"BJP leaders, who are making a hue and cry for the removal of so-called 'tainted ministers' from the United Progressive Alliance government, are themselves not clean, as seen in the case of the freight racket," he alleged.

He said he would talk to Prime Minister Manmohan Singh on the matter. Yadav, who himself detected overloading during a surprise check on the Millennium parcel train at Danapur last month, said he had directed the Railway Board chairman to initiate severe action against the guilty railway officials.