Nira Radia, a corporate lobbyist whose name figures in the 2G spectrum scam, was questioned by Indian Enforcement Directorate (ED) officials in New Delhi on Wednesday, media reports said.

She was summoned to the ED office, a law enforcement agency, where she arrived in the morning. Radia had not appeared to a summons issued earlier as she had cited health reasons then.

Enforcement Directorate, which is part of the department of revenue in India's ministry of finance, is also an economic intelligence agency responsible for enforcing economic laws and fighting economic crime in India.

Radia is being questioned on several issues including the possible violation of the Prevention of Money Laundering Act and her firms' alleged links with some of the telecom companies that were allocated 2G spectrum in 2008 by the then telecom minister A Raja, who recently resigned, Indo-Asian News Service quoted unnamed sources as saying in a report.

Tapes containing Radia's conversations with Raja, some industrialists and journalists have surfaced. The tapes were submitted as part of the evidence in a public interest litigation regarding the 2G spectrum row in the Supreme Court, the report said.

A Comptroller and Auditor General (CAG) report tabled in Indian parliament on November 16 had said the 2G spectrum allotment had caused a notional loss of several crores of rupees to the public exchequer.