NEW DELHI, Sept 11: A Sri Lankan Tamil rebel leader wanted for plotting Rajiv Gandhi’s assassination in 1991 has been arrested in Thailand and Indian Foreign Minister Pranab Mukherjee, due in Bangkok on an official visit on Thursday, is likely to seek his extradition, informed sources said on Tuesday.

Press Trust of India said top LTTE leader Kumaran Padmanathan, alias KP, was arrested on Monday and that India’s federal police, the CBI, has initiated moves for his expatriation.

Gandhi was killed by a woman suicide bomber at an election rally on May 21, 1991 in Sriperembudur in Tamil Nadu in apparent revenge for Indian army operations he had ordered in the rebel stronghold of Jaffna. Several alleged participants in the plot were killed in a police raid on their hideout near Bangalore and some others were arrested and later convicted by a special court.

India’s ruling Congress party is believed to be currently bracing for mid-term polls, in which case the emotive issue of Rajiv Gandhi’s assassination could help it in close a race.

The CBI has given details of the case against Mr Padmanathan to Thai police, and has sought its assistance in handing him over to face trial in India, the news agency said.

Details of the arrest are patchy but initial information suggested Mr Padmanathan was picke dup after three LTTE militants were detained last month in Thailand’s Ranong province while trying to buy guns and 45,000 rounds of ammunition.

The three militants and Padmanathan were suspected to be involved in a LTTE gun-running network based in Thailand, PTI quoted sources as saying.

Padmanathan has been declared one of the most wanted terrorists by Interpol as he is suspected to be a key person in LTTE’s global network for procuring weapons and other equipment.

Jane’s Defence Intelligence Review, the premier London- based defence magazine, recently reported that the LTTE had two international wings— KP Department and Aiyanna Group — that are engaged in global terrorist activities, PTI said.