An earthquake measuring 7 on the Richter scale jolted Taiwan yesterday. Two men were injured, but no major damage was reported.

One man in Ilan City in the east, and another man in Taoyuan County in the north, were injured after the quake struck at 12:08pm. Both men suffered minor injuries, local government reports said.

The man in Ilan City was hit by debris from his ceiling. He received four stitches on his forehead at a nearby hospital and returned home.

The Taoyuan County man's left leg was injured after it was struck by an iron bar that fell from the ceiling, which collapsed when a roof-top water tank overturned in the restaurant where he was eating. He also returned home after receiving treatment at a nearby hospital.

The quake's epicenter was about 110 kilometers off the Ilan City coast and 59 kilometers beneath the sea's surface, according to Taiwan's seismology center.

The quake shook the entire island. Ilan and the neighboring county Hualien registered the greatest intensity, at 5 on the Richter scale.

The quake had an intensity of 4 in Taipei and Taoyuan in the north, Taichung and Yunlin in central Taiwan, and Taitung in eastern Taiwan.

Seismologists told the public to be on alert for possible aftershocks - adding that aftershocks from a major earthquake may occur one hour, one day, one week, or even one month later.

In Taipei, the MRT subway system was shut down immediately after the earthquake struck. Service resumed about one hour later.

It was the strongest to shake Taiwan since the deadly 7.6 magnitude earthquake on September 21, 1999, that killed 2,415 people and injured more than 10,000 others.

Yesterday's earthquake was also the third strongest "undersea" earthquake since Taiwan began keeping records early in the 20th century. A temblor with a magnitude of 8.3 struck near the coast of Keelung, in the north, on April 12, 1910, and another 8.3 magnitude quake occurred on June 5, 1920, off the coast of Hualien in eastern Taiwan, Taiwan's fire administration bureau said.