Taiwan Semiconductor Manufacturing Co. evacuated factories following a 6.4 magnitude earthquake near the city of Chiayi that injured at least four people and suspended work at factories across the island’s south.

Chipmaker TSMC said on Tuesday that all its sites were operating following an overnight earthquake in southern Taiwan.

A magnitude 6.4 earthquake and resulting aftershocks in Chiayi early Tuesday morning triggered a shutdown and evacuation of TSMC's advanced process production lines in both the Southern and Central Science Parks.