NEW DELHI — Rescuers on Tuesday successfully drilled through to 41 men trapped inside a collapsed Himalayan tunnel, as a weekslong evacuation effort fraught with uncertainty enters its final stretch.

The men have been trapped since November 12 when the part of tunnel they were helping to construct in India’s northern Uttarakhand state gave way, blocking their only exit with more than 60 meters (200 feet) of broken rock, concrete and twisted metal.

The breakthrough follows a series of agonizing setbacks, during which rescue efforts were halted when the heavy machinery used to drill through the debris broke down, forcing workers to partially dig by hand and adopt other riskier methods to bring them to safety.

Engineers had previously attempted to excavate the debris in the exit shaft using heavy machinery, but were forced to abandon efforts late on Friday after the powerful US-made drill they were using broke down just meters from the trapped men.

Uttarakhand government’s executive engineer Avinash Kumar Saini told CNN that drilling had finally been completed after 17 days.

Rescuers were also simultaneously drilling downward through the unstable mountain terrain as a back up way to reach the trapped men. But in the end the initial plan proved successful.

With the drilling completed, rescuers then pushed a large pipe through the last part of the exit shaft for the men to be brought to safety.

“The work of laying pipes in the tunnel to take out the workers has been completed. Soon all the labor brothers will be taken out,” Pushkar Singh Dhami, Chief Minister Uttarakhand, wrote on X.

State district information officer Kirti Panwar a struck an optimistic tone that the workers would soon be reunited with their families.

“We are at the end of it all,” he said.

Mahi Shah, the brother-in-law of a laborer trapped inside, who is at the tunnel entrance, said rescuers have gone inside the tunnel.

“41 ambulances are ready here for people to come out. We have been told in about an hour they will all be out,” he told CNN.

Indrajeet Kumar, whose brothers Subodh and Biswajit were among those trapped said families were standing and waiting for their loved ones to walk out.

“They are not out yet, but we have been told to be ready to accompany them for medical aid soon,” he said.

Video broadcast on local television showed jubilant scenes outside the tunnel, with workers smiling and breaking into song after the drilling stopped. An ambulance could be seen driving into the tunnel.

The laborers – all migrant workers from some of India’s poorest states – have been receiving food, water and oxygen through a 53-meter (173 foot) pipe that has been inserted through the debris and authorities say they remain in good health.

Doctors on site have kept in regular contact with the men inside, giving them tips on how to remain positive and calm. Their families have been gathering at the tunnel exit each day to pray for their safe return.

The tunnel is part of Indian Prime Minister Narendra Modi’s Char Dham Highway route, a controversial multimillion dollar project to upgrade. the country’s transport network and improve connectivity to important Hindu pilgrimage sites in the region. — CNN