(Recasts with tsunami warning lifted, official comment)

JAKARTA, Oct 2 (Reuters) - A 6.2 magnitude earthquake rocked Indonesia's Sumatra island on Tuesday, but there were no reports of casualties or damage and a tsunami warning issued after the powerful undersea tremor was withdrawn.

The tremors sowed panic in the same area where a strong earthquake and series of aftershocks killed 25 people and damaged some 80,000 buildings last month.

The epicentre of Tuesday's quake lay at a depth of 20 km (12 miles), about 160 km (100 miles) southwest of Lais district in Bengkulu province, the meteorology agency said in a text message.

"It was quite strong. People panicked because they are still traumatised by the previous earthquakes. All of us ran out of the building," said Evi Nurhidayati, a police officer in Bengkulu.

Fauzi, the head of the seismology division at the meteorology agency, said buildings whose structure had been weakened by last month's quake could collapse because of the latest tremors.

"Even though today's quake was not really big, houses are vulnerable and we are worried about that," he said.

Since last month's earthquake, the area has been hit by a series of quakes and strong aftershocks, setting off tsunami warnings in Indonesia and other countries in the region.

Indonesia, which is situated along a belt of intense seismic activity known as the "Pacific Ring of Fire", was hit by a huge earthquake in December 2004, triggering a devastating tsunami in the Indian Ocean that killed more than 230,000 people in the region, including 170,000 Indonesians.

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