Survivors of an Indonesian earthquake that killed at least 268 people have appealed for food and water as rescuers picked through devastated villages with hopes of finding anyone alive fading.

The calls for help came as authorities warned that debris from landslides caused by the strong quake near the town of Cianjur in West Java needed to be cleared ahead of heavy rains forecast in the coming weeks, threatening a second disaster.

Helicopters will drop relief supplies to Indonesian villagers stranded after an earthquake crumpled homes in West Java, while others waited apprehensively to learn the fate of missing relatives.

More than 1,000 police officers have been drafted in to help rescue teams and there are still more than 150 people missing.

Recovery efforts will focus on Cugenang, one of the worst hit districts, where at least one village is believed to have been buried under a landslide, while helicopters will drop emergency supplies to two more cut off by blocked roads.

As authorities prepared to bring in more heavy machinery to clear the landslides, video images showed people digging the earth with their bare hands and tools such as hoes, sticks and crowbars.

"If it was just an earthquake, only the houses would collapse, but this is worse because of the landslide," said one man, who was searching for six missing relatives.

"In this residential area, there were eight houses, all of which were buried and swept away."

Rescuers are desperate to reach those trapped as soon as possible, said Henri Alfiandi, the chief of the search and rescue agency, who warned that chances of survival start to fade three days after a quake.

The mountainous terrain makes it difficult to deliver aid, forcing officials to trudge to the affected villages, said West Java Governor Ridwan Kamil.

President Joko Widodo called for earthquake-proof housing to be included in reconstruction efforts, during a visit to the town.

Two days after the quake flattened their homes, residents were still trying to retrieve priceless belongings including family photos, religious books and marriage certificates.

"Although some supplies have arrived, it is not enough. We got rice, instant noodles, mineral water but it's not enough," Mustafa, a 23-year-old resident of Gasol village, told AFP.

He had just dug through the rubble of an elderly neighbour's house at her request and carried clothes before returning to collect rice, a gas stove, canisters and frying pans.

"We have no clothes and we have not changed for days, so I am digging through the rubble to find some clothes," he said.

The government has dispatched tents and other supplies for the displaced but another resident appealed for more stocks because of shortages.

"My child has a fever and she can't eat. There are many children and elderly people here. Children need milk, diapers, food and medicine," said 30-year-old Yunisa Yuliani.

A man clears rubble from his home

Monday's quake was followed by more than 160 aftershocks and officials said that poor building standards led to many deaths.

There was an urgent need for immediate surgery as quake-damaged hospitals had limited capacity, Health Minister Budi Gunadi Sadikin said.

"My priority is no more deaths," he said. "The first priority is to make sure that badly injured patients are being taken care of, so they can survive.

Indonesia is vulnerable to landslides and flash floods in the rainy season, which has already begun and peaks in December in West Java.

The country's meteorology agency warned the town is prone to another catastrophe.

"We have to be vigilant over a potential second disaster, such as a landslide," Dwikorita Karnawati, head of the meteorology, climatology and geophysics agency told a press conference.

"The urgent step is to control heaps of fallen material," she said.

The agency's count of the tremor's aftershocks has increased to 145, with magnitudes ranging from 1.2 to 4.2, Karnawati said.

Cianjur's residents have begun to mourn loved ones, laying them to rest in accordance with their Islamic faith after authorities released them from morgues.

In February, an earthquake in West Pasaman on Sumatra killed several people and left the area's soil unstable and prone to rains that would cause landslides weeks later.

Ms Karnawati said rivers blocked by landslides or rubble sparked a flash flood in West Pasaman and warned the same could happen in Cianjur.

"We urgently need to clear materials and rubbles that block river flows in the upper hills".

Indonesia experiences frequent seismic and volcanic activity due to its position on the Pacific "Ring of Fire", where tectonic plates collide.