UPDATED 1.49pm: 132 people are trapped beneath the rubble of a Taiwan apartment tower that collapsed in a powerful earthquake.

The total is much higher than authorities had first estimated as rescuers combed the wreckage of the 17-storey building in the southern city of Tainan with sniffer dogs and acoustic equipment, looking for signs of life.

Rescue crews believed 29 of those still trapped could be reached more easily than the rest who were buried deeper in the rubble.

About 2000 firefighters and soldiers scrambled with ladders, cranes and other equipment to the ruins of the 17-floor residential building, which folded like an accordion onto its side after the quake struck.

The effects of the quake were felt throughout the island and surprised Madonna, who is on tour with her band in Taiwan.