Separatist rebels triggered a land mine Friday that killed at least five paramilitary soldiers and wounded 41 others in India's remote northeastern state of Assam, where a deadly separatist insurgency has long raged.

The soldiers were travelling in two buses when militants used a remote control device to trigger the explosion, said Luis Aind, district superintendent of police.

The blast occurred on a road passing through a dense jungle near the town of Goalpara, about 200 kilometres west of the state capital, Gauhati.

Five soldiers were killed instantly, Aind said. The wounded soldiers, at least 33 in critical condition, were taken to nearby hospitals.

Initial investigations indicated the rebels belonged to the National Democratic Front of Bodoland, an insurgent group that has fought for independence from India since 1986, Aind said.

But hours after the explosion a man who said he belonged to another separatist group, the United Liberation Front of Asom, or ULFA, called local television channels and claimed responsibility for the blast.

It was still unclear which group was responsible, officials said