Rescue teams are searching for a family of five feared trapped in a rockslide after Taiwan’s biggest earthquake in 25 years, which has left at least 12 people dead.

Two bodies have been found in the Taroko National Park, a tourist attraction famous for its rugged, mountainous terrain in Hualien County about 90 miles from Taipei.

At least four other victims were found in the park. Authorities have yet to verify the identities of the latest victims.

The You family had gone on a hike after visiting ancestral sites for the traditional grave-sweeping observances.

Wednesday’s 7.4-magnitude quake sent boulders and mud tumbling down mountains, blocking roads and smashing cars, and injured more than 1,000 people.

In the county seat of Hualien, crews were working to demolish the five-storey Tien Wang Hsing building, which was left leaning at a severe angle, one of scores of buildings damaged around the island.

Residents wearing motorcycle and construction helmets recovered legal documents and other documents before large cement-penetrating drills began bringing down the building.

A school teacher was killed in the building when she returned to her flat to find her cat just as an aftershock struck, bringing down more debris.

The small number of casualties and rapid response has been attributed to tightened construction safety standards and the replacement of older buildings with modern structures built to resist earthquakes.

Emergency services have upgraded their equipment and training, helped by civic groups such as the Red Cross and the Buddhist Tzu Chi charitable foundation, that have provided meals and set up shelters in school gymnasiums and other public spaces for those left homeless.

The powerful quake struck during the morning rush hour, sending schoolchildren rushing outdoors and families fleeing their flats through the windows.

The ground floors of some buildings collapsed, leaving them leaning at precarious angles.

Though the island is regularly rattled by earthquakes and generally well prepared, authorities did not send out the usual alerts because they were expecting a smaller quake.

Hualien was last struck by a deadly quake in 2018 which killed 17 people and brought down a historic hotel.

Taiwan’s worst recent earthquake struck on September 21, 1999, a magnitude 7.7 quake that caused 2,400 deaths, injured about 100,000 and destroyed thousands of buildings.