Panaji, Nov 18 (IANS) A self-defence instructor associated with the Sanatan Sanstha was Wednesday arrested for the Diwali-eve blast in Margao in which two members of the Hindu group were killed while carrying a bomb, police said.

Superintendent of Police Atmaram Deshpande said Dilip Managaokar, 39, was involved in planting an improvised explosive device (IED) that did not explode.

'He was involved in planting an improvised device at Sancoale (30 km from here) which did not explode,' Deshpande said at a press conference at the police headquarters.

'He has been remanded to seven days in police custody,' he added.

Deshpande added that Managaokar worked as a volunteer self-defence instructor at the Sanatan Sanstha's martial arts training school located at Dhamshe, a village in north Goa, 50 km from here.

The school, which imparted training in martial arts and horse-riding to the Sanatan Sanstha cadre, closed down three years ago. Mangaokar was a resident of Sanqulim in north Goa and was working as a weigh-bridge supervisor with a mining company.

Mangaokar's arrest by the special investigation team (SIT) takes to four the number of Sanatan Sanstha members held for the Oct 16 Goa blast. Two of the group's members, who are also accused in the Goa blast case, died of injuries when detonator-rigged gelatin sticks they were ferrying exploded while being taken to a crowded area in Margao, a south Goa town.

The police also found an unexploded improvised explosive device near the port town of Vasco a few minutes after the blast in Margao Oct 16.