YASHIO, Japan: Hopes faded for a 74-year-old man in Japan whose truck was swallowed by a sinkhole as a difficult rescue operation entered its third night on Thursday, with the chasm widening and locals urged to limit water use to aid efforts.

Japanese authorities have asked 1.2 million people to cut back on showers and laundry to prevent leaking sewage from aggravating an operation to rescue the truck driver, who rescuers have not communicated with since Tuesday afternoon.

The hole suddenly opened up at an intersection in the city of Yashio, about a 30-minute drive north of Tokyo, during the morning rush hour on Tuesday, swallowing the lorry.

The initial sinkhole, estimated at about 10 metres wide and six metres deep, has since merged with another.

“At around 2:30 am (on Thursday), the two holes became one, and with risk of another landslide or collapse of roads, we´ve been unable to use heavy machinery,” a fire department official told AFP.

Rescue efforts have been severely hampered by unstable ground around the hole. Water has also been seeping in.

The sinkhole and its vicinity remained cordoned off Thursday evening, surrounded by an array of factories that make the area something of an industrial hub.

“I always use that intersection to commute, which makes me think I could´ve been there when it happened,” Hiromasa Saito, a worker at a nearby metal processing factory, told AFP.

“We´re being told by the company to cut back on water, so we´re washing our hands less,” the 50-year-old added.