It's raining political victories for Mamata Banerjee and the the Trinamool, following the party's victory in the Kolkata Municipal Corporation. Eager to keep a key ally happy, the UPA-led government at the Centre has conceded to the Trinamool demand for a CBI probe into the recent Jnaneshwari Express derailment.

Initial objections of the West Bengal government notwithstanding, the Union government has decided to order a CBI probe into the train mishap in which 148 people were killed.

The decision has been taken as the incident had taken place on railway property and in such cases the concurrence of the state government was not required.

"We have decided to hand over the case to CBI under Section 5 of Delhi Police Special Establishment Act, under which the CBI functions," an official said

During the investigation, the CBI will be helped by the Central security agencies, Railway Protection Force and West Bengal government.

"Today the West Bengal government has conveyed to us that they will cooperate in the investigation," the official said.

Railway Minister Mamata Banerjee had alleged that there was a political conspiracy behind the train derailment and that could be unearthed only through a CBI probe.

However, West Bengal Home Secretary Samar Ghosh on Monday had dismissed the idea, saying, "The CID probe has progressed a great deal and the state government does not feel that a parallel inquiry is necessary."

Union home minister P Chidambaram had said on Monday that the Railways favoured a CBI probe, but the state government's view had not been received.

He had also said that the train derailment appeared to be an act of sabotage but it was not yet clear whether explosives were used to blast the tracks.

"The needle of suspicion points to Maoists or frontal organisations of CPI Maoists," Chidambaram had said.

The Section 5 of Delhi Police Special Establishment Act says that the Central Government may by order extend to any area (including Railways areas), 1[in 2[a State, not being a Union territory]] the powers and jurisdiction of member of the Delhi Special Police Establishment for the investigation of any offences or classes of offences.

The Centre's decision to hand over the probe to the can be largely seen as a reconciliatory gesture from the Congress after home minister P Chidambaram hadon Monday suggested that the train mishap had a Maoist hand behind it while saying that the CPI- this after Banerjee had called for a CBI probe alleging political conspiracy.

The Congress performance in the civic polls also necessitated attempts to refresh its alliance at the state level as Trinamool has won over two-thirds of the the total seats in the civic body.