A powerful earthquake struck off Indonesia’s popular resort island of Bali today, sending people fleeing from their homes and hotels in panic. No tsunami alert was issued, and there were no immediate reports of injuries.

Some roofs collapsed, and witnesses told local radio and television stations they saw cracks in the walls of buildings.

The US Geological Survey said the quake had a preliminary magnitude of 6.0 was centred 100 kilometres southwest of the island. It struck 60 kilometres beneath the ocean floor.

“It knocked me off my motorcycle,” said one resident, Miftahul Chusna.

Candy Juliani, a public relations officer for the Sanur Beach Hotel, said everything in the building was shaking.

“The guests ran from their rooms in panic,” she said.

“We have special emergency routes for this type of situation but everyone was so scared, they just ignored them.”

Indonesia straddles a series of fault lines that makes the vast island nation prone to volcanic and seismic activity.

A giant quake off the country on Dec. 26, 2004, triggered a tsunami in the Indian Ocean that killed 230,000 people, half of them in Indonesia’s westernmost province of Aceh.