Witnesses said people ran out of the roads in panic and some buildings collapsed.
Indonesia’s geological agency said the quake had a magnitude of 6.2 and was shallow, with a depth of 12km, centred on the northwest of the island.
It said it did not have the potential to cause a tsunami.
“Evacuees and people ran out of houses when they felt the strong shake of the 6.2 magnitude quake .... People are still traumatised. Some buildings were damaged further because of this quake,” Sutopo Purwo Nugroho, a spokesman for Indonesia’s disaster mitigation agency, said on Twitter.
The US Geological Survey measured the quake at magnitude 5.9.
It was the third big quake to hit Lombok in little over a week.
Buildings still standing on the island have been weakened after a 7.0 magnitude earthquake on Sunday and a 6.4 quake on 29 July.
The official death toll from Sunday’s quake stood at 131 on Wednesday, but a government-run news agency put the figure at 347.
Thousands have been left homeless on Lombok and in desperate need of clean water, food, medicine and shelter.
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