GAUHATI, India (AP) - Suspected rebels triggered a powerful explosion, derailing a freight train and setting more than a dozen oil tanker railcars on fire in India’s insurgency-wracked northeast, police said Tuesday.

There were no causalities in Monday night’s train attack, said Bhaskar Mahanta, a state inspector-general of police.

He blamed the attack on the United Liberation Front of Asom, which is fighting for an independent state for ethnic Assamese. It is the largest among dozens of militant groups in the region.

The ULFA didn’t claim responsibility for the attack in which a homemade bomb damaged railway tracks, causing some oil tanker cars to derail, and set more than a dozen of them or fire, said Mahanta. The Press Trust of India news agency says rail authorities used fire engines of the army and nearby industries to extinguish the blaze.

Intelligence reports, however, suggest the group was planning in response to the arrest of two leaders by India’s border guards last week when they returned from neighboring Bangladesh, he said.

The ULFA has also been linked to many acts of terrorism in Assam state, Mahanta said.

The freight train was transporting diesel and petrol from a state-owned refinery in Numaligarh, about 155 miles (250 kilometers) east of Gauhati, the capital of Assam state, to a northern Indian state, said Anup Baruah, a refinery spokesman.

Authorities suspended train service in the region because the tracks were blocked.

The separatists accuse the Indian government of taking the region’s natural resources while doing little for the indigenous people - most of whom are ethnically closer to people of Myanmar and China than to the rest of India.

More than 10,000 people have died in separatist violence over the past decade.