Indonesia issued a tsunami warning Wednesday after an earthquake with a preliminary magnitude of 8.9 hit waters off westernmost Aceh province.

People on Twitter said tremors were felt in Singapore, Thailand, Malaysia and India. High-rise apartments and offices on Malaysia's west coast shook for at least a minute.

The Pacific Tsunami Warning Center in Hawaii said a tsunami watch was in effect for Indonesia, India, Sri Lanka, Australia, Myanmar, Thailand, the Maldives and other Indian Ocean islands, Malaysia, Pakistan, Somalia, Oman, Iran, Bangladesh, Kenya, South Africa and Singapore.

A tsunami watch means there is the potential for a tsunami, not that one is imminent.

The U.S. Geological Survey said the powerful quake was centered 20 miles (33 kilometers) beneath the ocean floor around 308 miles (495 kilometers) from Aceh's provincial capital.

Said, an official at Indonesia's Meteorology and Geophysics Agency who goes by only one name, said a tsunami warning has been issued.

Indonesia straddles a series of fault lines that makes the vast island nation prone to volcanic and seismic activity.

A giant 9.1-magnitude quake off the country on Dec. 26, 2004, triggered a tsunami in the Indian Ocean that killed 230,000 people, nearly three quarter of them in Aceh.

【新聞快訊】據(jù)美國(guó)地質(zhì)勘探局網(wǎng)站消息，北京時(shí)間2012年4月11日16時(shí)38分，北蘇門(mén)答臘西海岸發(fā)生里氏8.9級(jí)地震，震源深度33公里。印尼氣象與地球物理局官員表示，他們已向28個(gè)國(guó)家發(fā)布海嘯警報(bào)。

由于印尼位于太平洋地震帶和歐亞地震帶的交界處，大陸板塊在這里交接，地震和火山活動(dòng)頻繁，每年發(fā)生的大小地震不下數(shù)千次。印尼亞齊省是2004年印度洋海嘯的重災(zāi)區(qū)，海嘯奪走了該省近17萬(wàn)人的生命。