Japan was assessing damage on Tuesday and warning residents of potential aftershocks after a magnitude 7.5 earthquake struck late Monday, causing injuries, minor damage, and a tsunami in Pacific coastal communities.

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

Prime Minister Sanae Takaichi told reporters that an emergency task force had been formed to urgently assess the damage. "We are putting people’s lives first and doing everything we can," she stated.

During a parliamentary session on Tuesday, Takaichi pledged the government would continue its utmost efforts and reminded people to protect their own lives.

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

A tsunami of up to 70 centimeters (2 feet, 4 inches) was recorded at Kuji Port in Iwate Prefecture, just south of Aomori, and waves up to 50 centimeters hit other communities in the region, the Japan Meteorological Agency reported. NHK noted that the waves damaged some oyster rafts.

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

Chief Cabinet Secretary Minoru Kihara said about 800 households were without electricity, and Shinkansen bullet trains and some local lines were suspended in parts of the region early Tuesday. East Japan Railway said it aimed to resume high-speed train services in the area later that day.

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

Approximately 480 residents took shelter at Hachinohe Air Base, and 18 defense helicopters were mobilized for damage assessment, Defense Minister Shinjiro Koizumi said.

About 200 passengers were stranded overnight at New Chitose Airport in Hokkaido, NHK reported. Part of a domestic terminal building was unusable on Tuesday after sections of its roof 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 its water level remained within the normal range and there were no safety concerns. No abnormalities were found at other nuclear power plants or spent fuel storage facilities, the NRA added.

The JMA warned of possible aftershocks in the coming days. It noted a slight increase in the risk of a magnitude 8 earthquake and a potential tsunami along Japan’s northeast coast from Chiba, just east of Tokyo, to Hokkaido. The agency urged residents in 182 municipalities in the area to review their emergency preparations over the next week, clarifying that the warning was not a prediction of a major quake.

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

"People should prepare, assuming a disaster like that could happen again," said JMA official Satoshi Harada.

Smaller aftershocks continued on Tuesday. The U.S. Geological Survey reported a magnitude 6.6 tremor followed by a 5.1 quake in the hours after the initial shock.