Japanese rescuers raced against time on Thursday to search for survivors of a devastating New Year's Day earthquake as the crucial three-day window since the disaster closed.

Survival rates significantly drop once 72 hours have passed, emergency responders say.

Disaster relief pledges

The 7.6 magnitude quake hit the Noto peninsula on Japan's western coast on Monday. At least 81 people have thus far been killed and at least 79 others are still unaccounted for. More than 150 have been rescued.

"There are many people left behind in the collapsed buildings, waiting to be rescued," Japanese Prime Minister Fumio Kishida said at a press conference.

"We will use all of our efforts to rescue as many people as possible by this evening, when 72 hours will pass since the disaster."

Kishida pledged roughly 4 billion yen ($28 million; €25.5 million) of the national budget on Thursday for disaster relief.

What's hampering rescue operations?

Rescue efforts have been complicated by difficult weather conditions and damaged roads that have cut off many of the worst-hit areas. Though material aid has been trickling into the Noto peninsula since the quake, survivors who have been evacuated remain largely in need of more supplies.

Some 3,000 meals and 5,000 bottles of water were delivered as of Wednesday to the peninsula city of Wajima. But local mayor Shigeru Sakaguchi said this was not enough for the city's 11,000 evacuees.

"First and foremost, it's the road — severed roads are hampering not just aid supplies, but also the recovery of electricity, water, mobile signals and other lifeline infrastructures," he said.

The government has pledged to proactively provide supplies, rather than waiting for official requests from local authorities.

It also opted to transfer aid via sea, though this route also had its limitations, as larger ships have been unable to dock due to the seabed being buckled by the quake.

rmt/nm (AP, Reuters)