A major 7.5 quake struck off the Indonesian island of Sulawesi

A major 7.5 quake struck off the Indonesian island of Sulawesi on Friday, prompting a tsunami alert hours after a milder quake brought down houses in the same area, and officials expect further damage.

The warning was lifted within the hour, but officials asked people to remain on the alert as a number of moderate aftershocks hit.

“We advise people to remain in safe areas, stay away from damaged buildings,” Sutopo Purwo Nugroho, spokesman for the National Disaster Mitigation Agency, said in a televised interview.

He added that the national agency in Jakarta was having difficulties reaching some authorities in the area.

The US Geological Survey put the magnitude of the second quake at a strong 7.5, after first saying it was 7.7.