(Image source from: HipHop RX)

A powerful 7.5 magnitude earthquake off the coast of the Indonesian island of Sulawesi on Friday evening has triggered a tsunami, killing almost 400 people and injuring nearly 540 people.

The temblor crashed into at least two cities, including the popular tourist resort of Palu.

In Palu, the capital of central Sulawesi province, the tsunami up to 2 meters high swept away houses. It as well struck a smaller city Donggala, closer to the epicenter of the quake 80 kilometers (50 miles) away.

Based on hospital reports, the National Disaster Mitigation Agency put the official death toll at 384, almost all of them in the hard-city of Palu.

The death toll continues to rise as rescuers retrieve bodies in the stricken city of Palu

"When the (tsunami) threat arose yesterday, people were still doing their activities on the beach and did not immediately run and they became victims," agency spokesman Sutopo Purwo Nugroho said on Saturday.

The city's airport was closed after its runway and a control tower was battered in the quake. Officials said they were rushing to reopen the airport to allow aid to come in.

Due to power outages, communications in the area have been cut, hampering rescue and clean-up efforts.

A video circulating on the social media showed a powerful wave hitting Palu with people screaming and fleeing in fear. The wave damaged several buildings, including a mosque.

Indonesia geophysics agency says Sulawesi quake caused a tsunami. This video is doing the rounds. We believe it is real. pic.twitter.com/7xDzzRuj5v

— David Lipson (@davidlipson) September 28, 2018

Indonesian president Joko Widodo said the military had been called into the disaster-struck region to help search-and-rescue teams reach victims and retrieve bodies.

Nugroho described the damage as "extensive," adding that thousands of hospitals, houses, shopping malls, and hotels had collapsed, while a bridge had also been washed away.

By Sowmya Sangam