Authorities in the city of Petropavlovsk-Kamchatsky declared a state of emergency on Wednesday after a powerful magnitude 8.8 earthquake struck off Far East Russia’s Kamchatka Peninsula, triggering tsunami waves and dozens of aftershocks.

The quake, one of the strongest ever recorded globally, struck at 8:24 a.m. local time off the coast of Petropavlovsk-Kamchatsky. The epicenter was located 149 kilometers (93 miles) southeast of the city at a depth of 17 kilometers (10.6 miles), according to geologists at the local branch of Russia’s Academy of Sciences.

More than 50 aftershocks followed the initial quake, and seismologists warn that tremors up to magnitude 7.5 could occur in the coming days or weeks.

Petropavlovsk-Kamchatsky Mayor Yevgeny Belyaev said public services were on high alert and damage inspections were underway. A portion of a kindergarten facade collapsed, he said, but no injuries were reported. Most damage so far has been cosmetic, although elevator outages were reported in some newly built residential buildings, Belyaev added.

Temporary shelters were set up for residents unwilling to return home due to the continued risk of aftershocks. Officials advised people to avoid beaches and shorelines around Avacha Bay, a popular spot for locals and tourists.