A close associate of Congress MP Karti Chidambaram was arrested on Wednesday by the Central Bureau of Investigation in a bribery case, reported DD News.

Officials of the central agency arrested S Bhaskar Raman, who is also named as the first accused in the case, after questioning him in Chennai, reported The Hindu.

The development came a day after the Central Bureau of Investigation booked Karti Chidambaram, the son of former Union minister P Chidambaram, for allegedly taking bribes to arrange visas for Chinese citizens.

The central agency has alleged that Karti Chidambaram had received Rs 50 lakh as “illegal gratification” to arrange visas for over 250 Chinese citizens during the Congress-led United Progressive Alliance regime.

The Central Bureau of Investigation alleged that Vikas Makharia, the associate vice president of thermal power plant Talwandi Sabo Power, had approached Chidambaram’s “close associate/front man” Raman to reissue project visas for the Chinese workers employed by him, reported PTI.

Project visas are special type of visas for employees of the power and steel sector. Guidelines for these visas were issued during P Chidambaram’s tenure as the home minister in 2010, but there was no provision to reuse them, according to the first information report.

“As per prevalent guidelines, deviation in rare and exceptional cases [for reuse] could be considered and granted only with the approval of the home secretary,” it said. “However, in view of the above circumstances, the deviation in terms of reuse of project visas is likely to be approved by the then home minister.”

Makharia had allegedly submitted a letter seeking approval to reuse the project visas to the home ministry on July 30, 2011. A month later on August 17, Makharia sent a copy of the letter to Bharti, who forwarded it to Karti Chidambaram, the FIR alleged.

“Bhaskar Raman after discussion with P Chidambaram, the then home minister, demanded an illegal gratification of Rs 50 lakh for ensuring the approval,” it alleged.