New Delhi, Aug 17: Outlawed militant group Kanglei Yawol Kanna Lup (KYKL) is suspected to be behind yesterday's blast at ISKCON complex in Imphal, a senior Union Home Ministry official said here today.

Though none has claimed responsibility for the blast which claimed four lives and left 66 others, including two Americans, injured, the hand of KYKL is suspected, he said.

KYKL, which was formed over a decade ago, has been indulging in extortions and are said to have demanded a hefty amount from the ISKCON's chief priest.

Refusal to pay the amount led to the lobbing of "Chinese-make hand grenades" at the Sankirtan place from outside the complex when the shrine was teeming with Janmasthami devotees, the official said.

He said the Centre was in constant touch with the Manipur Chief Secretary and Director General of Police and reviewing the situation from time to time.