TOKYO (AP) — Japan was assessing damage Tuesday and cautioning people of potential aftershocks after a late-night 7.5 magnitude earthquake caused injuries, light damage and a tsunami in Pacific coastal communities.

At least 33 people were injured, one seriously, the Fire and Disaster Management Agency said. Most of them were hit by falling objects, public broadcaster NHK reported.

Prime Minister Sanae Takaichi told reporters an emergency task force was formed to urgently assess damage. “We are putting people’s lives first and doing everything we can,” she said.

At a parliamentary session Tuesday, Takaichi pledged the government would continue its utmost effort and reminded people they have to protect their own lives.

The 7.5 magnitude quake struck around 11:15 p.m. in the Pacific Ocean, around 80 kilometers (50 miles) off the coast of Aomori, the northernmost prefecture of Japan’s main Honshu island. The U.S. Geological Survey measured the quake at 7.6 magnitude and said it occurred 44 kilometers (27 miles) below the surface.

A tsunami of up to 70 centimeters (2 feet, 4 inches) was measured in Kuji port in Iwate prefecture, just south of Aomori, and waves up to 50 centimeters struck other communities in the region, the Japan Meteorological Agency said. NHK reported the waves damaged some oyster rafts.

The agency lifted all tsunami advisories by 6:30 a.m. Tuesday.

Chief Cabinet Secretary Minoru Kihara said about 800 homes were without electricity and Shinkansen bullet trains and some local lines were suspended in parts of the region in the early hours of Tuesday. East Japan Railway said it is aiming to resume bullet trains in the region later Tuesday.

Power was mostly restored by Tuesday morning, according to the Tohoku Electric Power Co.

About 480 residents sheltered at Hachinohe Air Base and 18 defense helicopters were mobilized for a damage assessment, Defense Minister Shinjiro Koizumi said.

About 200 passengers were stranded for the night at New Chitose Airport in Hokkaido, NHK reported. Part of a domestic terminal building was unusable Tuesday after parts of its ceiling cracked and fell to the floor, according to the airport operator.

The Nuclear Regulation Authority said about 450 liters (118 gallons) of water spilled from a spent fuel cooling area at the Rokkasho fuel reprocessing plant in Aomori, but that its water level remained within the normal range and there was no safety concern. No abnormalities were found at other nuclear power plants and spent fuel storage facilities, the NRA said.

JMA cautioned about possible aftershocks in the coming days. It said there is a slight increase in risk of a magnitude 8-level quake and possible tsunami occurring along Japan's northeastern coast from Chiba, just east of Tokyo, to Hokkaido. The agency urged residents in 182 municipalities in the area to monitor their emergency preparedness in the coming week, reminding them that the caution is not a prediction of a big one.

Monday's quake occurred just north of the coastal region where the magnitude 9.0 quake and tsunami in 2011 killed nearly 20,000 people and destroyed the Fukushima Daiichi nuclear power plant.

“You need to prepare, assuming that a disaster like that could happen again," JMA official Satoshi Harada said.

Smaller aftershocks were continuing Tuesday. The U.S. Geological Survey reported a magnitude 6.6 and later a 5.1 quake in the hours after the initial temblor.