The Philippines lifted a tsunami alert early on Sunday as waves receded from a magnitude 7.4 earthquake that struck the south of the country, triggering coastal evacuations and some waves there and in Japan.
There were no initial reports of casualties or serious damage from the quake in the Mindanao region, although some residents reported damage to buildings in the area, which is less populated than some parts of the archipelago.
More than 500 aftershocks were recorded, and the Philippines' Institute of Volcanology and Seismology (Phivolcs) urged caution as people resumed normal activities.
"The tsunami threat associated with this earthquake has now largely passed the Philippines," Phivolcs said in a statement, but it advised people in threatened communities to heed instructions from local authorities.
It had earlier urged people living near the coast of Surigao Del Sur and Davao Oriental provinces to move inland.
The national disaster agency said it was assessing the impact of the quake, with a team on the ground collating information.
The Philippine Coast Guard put all its vessels and aircraft on alert for potential dispatch.
"We started going back to our homes early on Sunday, although we are still shaking because of aftershocks," said Julita Bicap, 51, a front desk staffer at GLC Suites hotel in the seaside town of Bislig, after power was restored around 5 a.m. local time (2100 GMT)
"There are aftershocks even now. Last night we were at the evacuation center including my two foreigner guests. One of them came back to the hotel already," Bicap told Reuters, adding that she noticed a small crack in the hotel's front wall.
The largest aftershock was magnitude 6.5, according to the European-Mediterranean Seismological Centre.
Earthquakes are common in the Philippines, which sits on the "Ring of Fire," a belt of volcanoes circling the Pacific Ocean that is prone to seismic activity.
Scores of residents were seen in an evacuation center in photographs posted on social media by the authorities in Hinatuan province, 30 kilometers from the quake's epicenter.
Philvolcs' Hinatuan-Bislig Bay station recorded maximum waves of 0.64 meter. Japan's Hachijojima island, some 290 kilometers south of Tokyo, recorded waves of 40 cm, the Japan Meteorological Agency said.
The U.S. Tsunami Warning System had initially warned of waves of up to 3 meters above the usual high tide level.
The quake, which struck at 10:37 p.m. local time (1437 GMT) on Saturday, was at a depth of 25 kilometers, Philvolcs said.
James Soria, who owns a small hotel in Hinatuan, said there had been significant damage to his home.
"It's shaking again here now," he told Reuters before the call was disconnected as another aftershock hit.
Cosme Calejesan, 47, said there had been damage to his house in Surigao City, 185 kilometers from the epicenter, but the structure was intact.
"I was already asleep, but I was woken up by the creaking sounds of my cabinets when the tremor occurred," he said. "It was frightening. It was sudden and abrupt, and I was worried for my children."