A huge fire broke out at an oil field near popular ecotourism spots in northeastern India on Tuesday, after gas that had spewed for two weeks from a blown-out well ignited, officials said.

The gas well at an oil field managed by state-owned Oil India started leaking in late May in Tinsukia district of Assam state, and the firm said late last week gas was still flowing "uncontrollably".

The explosion sent bright orange flames and huge, black plumes of smoke high into the sky
The explosion sent bright orange flames and huge, black plumes of smoke high into the sky AFP / Partha Sarathi DAS

Tuesday's explosion sent bright orange flames and huge, black plumes of smoke high into the sky, visible 10 kilometres (six miles) from the oil field, locals told AFP.

"While the clearing operations were on at the well site, the well caught fire," Oil India said in a statement, adding that a firefighter suffered "minor injuries".

Around 200 engineers and workers -- including a team of experts who arrived from Singapore on Monday -- are trying to stem the leak within four weeks, the company added.

Indian policemen ask people to move to a safer location following the explosion at a facility operated by the state-owned Oil India Limited (OIL) in Tinsukia district in Assam state
Indian policemen ask people to move to a safer location following the explosion at a facility operated by the state-owned Oil India Limited (OIL) in Tinsukia district in Assam state AFP / Partha Sarathi DAS

Villagers fled in fear, and said five of their homes had caught fire.

"The situation is very bad. It is spreading. I knew it was going to happen," local environmentalist Niranta Gohain told AFP over the phone from the site.

A huge fire has broken out at an oil field in northeastern India
A huge fire has broken out at an oil field in northeastern India AFPTV / Partha Sarathi DAS

The company called for help from the army after locals allegedly attacked its vehicles after Tuesday's explosion, spokesman Tridiv Hazarika said.

Water was being pumped to the well over the past two weeks to prevent the gas catching fire.

Assam's Chief Minister Sarbananda Sonowal said firefighters, police and the army were being sent to the site, which is 500 kilometres east of Guwahati, the state's biggest city.

Environmentalists were increasingly worried about the impact of the gas leak.

The well was producing 100,000 standard cubic metres per day (SCMD) of gas from a depth of 3,870 metres (4,234 yards) before the blowout in May, according to Oil India.

Just one kilometre from the field is Maguri-Motapung wetlands, an ecotourism site. State-owned sanctuary Dibru Saikhowa National Park -- renowned for migratory birds -- is about 2.5 kilometres away.

Authorities had established an exclusion zone of 1.5 kilometres and about 2,500 people had been evacuated from their homes.