At least 91 people were killed when Indonesia's resort island of Lombok was hit by a powerful magnitude 7.0 earthquake on Sunday, triggering widespread panic as thousands fled their homes for emergency shelters as buildings collapsed.

The death toll is expected to rise with hundreds injured and thousands of houses damaged, the National Disaster Mitigation Agency said in a statement today.

Singapore Law and Home Affairs Minister K Shanmugam, who was on the 10th floor of a hotel in the Lombok town of Mataram at the time of the quake, wrote on Facebook that his room shook violently and walls cracked.

"It was quite impossible to stand up. Heard screams. Came out, and made my way down a staircase, while building was still shaking. Power went out for a while. Lots of cracks, fallen doors," he wrote.

Most of the victims were killed by falling rubble in northern and western parts of Lombok.

An initial tsunami warning of waves of up to half a metre was issued following the quake but later withdrawn.

Lombok was hit by another powerful 6.4 quake a week earlier on July 29, killing 17 people and injuring hundreds of people.

More than 100 aftershocks have rattled Lombok since the quake, which was so powerful it was felt on the neighbouring island of Bali.

"The night condition and some disconnected communication lines pose some challenges in the field. Death count is expected to increase still," the disaster management agency said.

I Nyoman Sidakarya, head of Mataram's search and rescue agency, told TvOne, authorities will evacuate around 700 tourists and local residents from the nearby Gili Islands.

"We will evacuate people off of the three Gili islands. Some of them are hurt and are in shock," Sidakarya said in the televised interview.

One person in Gili Air was killed, he said, but details about the victim is unknown yet.

Saffron Amis, a British student visiting the Gili Islands off the northwest coast of Lombok, told Reuters by text message that dozens of tourists were evacuated to a hill after the quake.

The quake struck Lombok in the early evening at a depth of 10km (6 miles).

Most of Lombok suffered power cuts, local media reported.

Travellers at the international airports in Lombok and Bali were thrown into panic and there was minor damage to the buildings but operations were not disrupted, officials said.

The quake was felt for several seconds in Bali, where people ran out of houses, hotels and restaurants.

"All the hotel guests were running, so I did too. People filled the streets," said Michelle Lindsay, an Australian tourist. "A lot of officials were urging people not to panic."

Other witnesses said the initial quake grew in intensity over several seconds, rattling windows and doors, and there were many aftershocks.

- Reuters