By Ahmadi
SINABANG, Indonesia (Reuters) - A major earthquake of 7.7 magnitude struck off the coast of Aceh in north-western Indonesia on Wednesday, triggering panic and power blackouts, but no deaths were reported and a tsunami alert was later lifted.
Neighbouring Thailand and Malaysia also cancelled tsunami warnings.
A Reuters photographer in Sinabang on Simeulue island, south of Aceh and close to the epicentre, said electricity was cut in the area and that he saw four injured people, including a child with a head wound who had been hit by fallen masonry.
The National Disaster Mitigation Agency said 12 people were being treated in a hospital in Sinabang, with injuries caused by fallen electricity poles, roof tiles and shattered glass.
President Susilo Bambang Yudhoyono expressed relief the island of Sumatra appeared to have escaped major devastation.
"Thanks be to God the quake did not cause a tsunami or any significant damage," Yudhoyono told a briefing at Halim airport in the Indonesian capital Jakarta, about 1,200 km (750 miles) southeast of the quake's epicentre.
Aceh Governor Irwandi Yusuf said earlier there had been no reports of damage or casualties so far, although it would take time to reach remote areas.
"I am on the coast now, some people had gone to take refuge on higher ground but now they have returned to their homes," Yusuf told Metro TV.
The resource-rich island of Sumatra, where Aceh is located, is an important supplier of commodities such as rubber, palm oil and liquefied natural gas (LNG), but there were no immediate reports of delays in shipments because of the quake.
In December 2004, a magnitude 9.15 quake off Aceh triggered an Indian Ocean tsunami that killed about 226,000 people in Indonesia, Sri Lanka, India, Thailand and nine other countries.
Wednesday's quake, which struck around 5:15 a.m. (11:15 p.m. British time), was centred 200 km (125 miles) west-northwest of the coastal town of Sibolga and was at a depth of 31 km, the U.S. Geological Survey said. The epicentre was around 215 km from Medan, the largest city on Sumatra.
There were at least three aftershocks after the initial major quake.
ELECTRICITY POLES SWAY
The Hawaii-based Pacific Tsunami Warning Centre initially warned the quake could generate a local tsunami, but later cancelled its tsunami watch, saying: "Sea level readings indicate that a significant tsunami was not generated."
Indonesia's meteorology agency lifted its tsunami warning, but officials said that a tiny tsunami of 3 cm (1 inch) had been detected at Sinabang and one of 40 cm at nearby Banyak island.
"People are still seeking refuge in safe places, some of them are suffering from trauma," a sub-district head on Banyak island said, adding that some boats had been damaged and the sea was rougher than usual.
"Sea water rose about 30-40 centimetres and flooded people's homes. But people ran for their lives and there were no casualties," he said, adding about 7,000 people lived in the area.
A Metro TV reporter in the Sibolga area of North Sumatra said that he fell off his motorbike when the quake struck and the force left electricity poles swaying for minutes afterwards.
The country's disaster agency said about 80 percent of small electricity terminals in North Sumatra province were damaged by the quake, although 25 percent had been restored.
Hamid Sarong, a resident of Aceh's provincial capital Banda Aceh, which was devastated by the 2004 tsunami, said the quake was felt while people in the staunchly Muslim province were at dawn prayers, although there was no panic.
In the Singkil district of Aceh the dome of a mosque was flattened and another mosque damaged in Kuala Baro, said local official Sukri Murni.
Sumatra lies along the Pacific "Ring of Fire," one of the world's most active seismic faultlines, and is frequently hit by earthquakes.
A 7.6 magnitude quake struck last September off the city of Padang, southeast of Wednesday's epicentre, killing more than 1,000 people.
(Additional reporting by Ed Davies, Telly Nathalia and Olivia Rondonuwu in Jakarta, and Reza Munawir in Banda Aceh; Editing by Sugita Katyal)
