Indonesiamounted a rescue operation Monday to reach more than 500 hikers and guides stranded by landslides on an active volcano on Lombok, a day after a powerful earthquake struck the holiday island.

Helicopters and search teams on foot have been deployed to scour the slopes of Mount Rinjani, which is crisscrossed with hiking routes popular with tourists, while rescuers have made airdrops of food supplies to those stranded.

Tonnes of rock and mud were dislodged on the mountain in the 6.4-magnitude quake, which struck early Sunday and was followed by scores of aftershocks, leaving hikers with no easy way down to safety.

“There are still 560 people trapped,” said the head of Rinjani national park Sudiyono, who goes by one name.

Those believed to be stranded include citizens from the United States, France, The Netherlands, Thailand and Germany, as well as many other countries, search and rescue officials said.

At least 16 people were killed in the earthquake across affected areas of Lombok, while hundreds of buildings were destroyed.

Food for two days

The rescue operation on Mount Rinjani is likely to run until at least Tuesday and a military helicopter has dropped supplies at several spots on the mountain, according to search and rescue agency officials.

“For supplies, they can still survive for another one to two days,” Agus Hendra Sanjaya, spokesman for Mataram’s search and rescue agency, told AFP.

No hikers are injured, he added.

Rising some 3,726 metres (12,224 feet) above sea level, the peak is the second-tallest volcano inIndonesiaand a favourite among sightseers keen to take in its expansive views.

Hiking trails on the mountain were closed following the quake due to fear of further landslides.

The epicentre of the earthquake was 50 km (30 miles) northeast of Lombok’s main city Mataram, the United States Geological Survey said, far from the main tourist spots on the south and west of the island.

The initial tremor was followed by two strong secondary quakes and more than 100 aftershocks.

Some 160 people were injured, as a result, said Mohammad Rum, head of West Nusa Tenggara disaster agency.

Among the dead are one Malaysian, with six injured, the Malaysian foreign ministry said.

President Joko Widodo visited the affected site on Monday and promised financial support for people who had lost their homes.

“We must be aware that our country is in the Ring ofFire, so people need to be prepared to face any disaster,” Widodo said.

Indonesia, one of the most disaster-prone nations on earth, straddles the so-called Pacific ‘Ring ofFire‘, where tectonic plates collide and a large portion of the world’s volcanic eruptions and earthquakes occur.

In 2004 a tsunami triggered by a magnitude 9.3 undersea earthquake off the coast of Sumatra in westernIndonesiakilled 220,000 people in countries around the Indian Ocean, including 168,000 inIndonesia. (AFP)

• An Indonesian village security officer examining the debris of houses, after a 6.4 magnitude earthquake struck, in Lombok. At least 16 people were killed in the earthquake after it struck Lombok early on July 29, while hundreds of buildings were destroyed. AULIA AHMAD / AFP