Uttarakhand government has sought technical assistance from Coal India to expedite the rescue operation to evacuate 41 labourers, including three from Bengal, trapped since November 12 following the collapse of an under-construction tunnel in Uttarkashi.

Sources said that Coal Mine Planning and Design Institute Limited (CMPDI) has asked the Eastern Coalfields Limited (ECL), which has vast experience in handling such challenging rescue operations, to send its expert technicians to Uttarkashi immediately.

A team from CMPDI is already on the spot and doing a survey to guide the NDRF team working there.

The ECL, a Coal India subsidiary, carried out a challenging rescue operation in 1989 to save 65 miners trapped inside a flooded underground mine at Mahabir Colliery in West Burdwan's Raniganj. The ECL rescue team sent a capsule lift inside the mine by drilling a hole and rescued the miners.

Sources said that inspired by the rescue operations by the ECL 34 years ago, the Uttarakhand government decided to call in the coal major to help them evacuate those trapped in the tunnel collapse.

Niladri Roy, director (technical), said the rescue team in Uttarkashi was drilling an 80-metre hole from the surface to reach the trapped miners.

"They wanted to know about the techniques used in the rescue operation at Mahabir Colliery in 1989. The ECL and CMPDI team reached the site on Wednesday and already started their job in Uttarkashi. In the past, we have provided technical assistance in a rescue operation in Assam," said Roy.

The three-decade-old incident got fresh publicity after the recent release of the movie Mission Raniganj starring Akshay Kumar. Its story was based on the 1989 accident and its challenging rescue.

Sources said the drilling operation had begun and it would take at least 12 to 14 hours to reach trapped workers.