PALU, Indonesia (Updated) -- The powerful earthquake and tsunami that hit Indonesia's central Sulawesi province has claimed many victims, a disaster official said Saturday, as rescuers raced to reach the region and an AP reporter saw numerous bodies in a hard-hit city.
Disaster officials haven't released an official death toll but reports from three hospitals seen Saturday by The Associated Press listed 18 dead.
Dawn revealed a devastated coastline in central Sulawesi where the 3-meter high (10 foot) tsunami triggered by a magnitude 7.5 earthquake Friday smashed into two cities and several settlements.
Disaster agency spokesman Sutopo Purwo Nugroho said in a television interview there are "many victims."
In Palu, the capital of Central Sulawesi province, a large bridge spanning a coastal river had collapsed and the city was strewn with debris.
The city is built around a narrow bay that apparently magnified the force of the tsunami waters as they raced into the tight inlet.
An AP reporter saw bodies partially covered by tarpaulins and a man carrying a dead child through the wreckage.
Indonesian TV showed a smartphone video of a powerful wave hitting Palu, with people screaming and running in fear. The water smashed into buildings and a large mosque already damaged by the earthquake.
Communications with the area are difficult because power and telecommunications are cut, hampering search and rescue efforts.
Nugroho said the runway of Palu's airport is not damaged and essential aircraft can land there.
Sutopo said the military was deploying troops to Palu and Donggala and the national police were also mobilizing to help the emergency response, as well as personnel from the search-and-rescue and disaster agencies.
"People are encouraged to remain vigilant," Sutopo said. "It is better not to be in a house or building because the potential for aftershocks can be dangerous. People are encouraged to gather in safe areas. Avoid the slopes of hills."
Palu's airport halted operations for 24 hours due to earthquake damage, according to AirNav, which oversees airline traffic in Indonesia.
Mirza Arisam, a resident of Kendari, the capital of neighboring Southeast Sulawesi, said his uncle and his family of five, including three children, were on vacation in Palu and he has been unable to contact them since the tsunami hit.
After the 7.5 quake struck, television footage showed people running into the streets. Women and children wailed hysterically in a video distributed by the disaster agency, which also released a photo showing a heavily damaged department store.
"It was so strong. The strongest I ever felt. We all ran out of buildings," said Yanti, a 40-year-old housewife in Donggala who goes by a single name.
"All the things in my house were swaying," another Donggala resident, Mohammad Fikri, said of the earlier 6.1 quake.
UN spokesman Stephane Dujarric said UN officials were in contact with Indonesian authorities and "stand ready to provide support as required."
Indonesia is prone to earthquakes because of its location on the "Ring of Fire," an arc of volcanoes and fault lines in the Pacific Basin.
In December 2004, a massive magnitude 9.1 earthquake off Sumatra in western Indonesia triggered a tsunami that killed 230,000 people in a dozen countries. (AP)