Reeling under heavy losses in flush-out operations carried out since Monday by the Royal Bhutan Army, ULFA chief Paresh Barua today said Bhutan was acting under ‘‘tremendous’’ pressure from India.Barua said the outfit’s central and general headquarters had been totally demolished and at least one leader was killed on day one of the military attack. Barua has been calling up local newspaper offices from an undisclosed destination; intelligence agencies were certain he was holed up in Bangladesh. Barua alleged that Indian Army personnel, in disguise, were also engaged in the flush-out operations and that the forces were using mortar fire and rocket-propelled grenades (RPGs) to demolish their camps. ‘‘The Bhutan government has committed a breach of trust as we were still talking with them on shifting base from that country. They (the Bhutan authorities) are under tremendous pressure from India,’’ Barua said. The ULFA chief claimed that the strikes had targeted several women and children living in the camps. At least five children had been killed on the first day of the atttac, he said.