An earthquake of magnitude 7.4 struck the Northern Molucca Sea off Indonesia's historic spice island of Ternate on Thursday, the United States Geological Survey (USGS) said, triggering a tsunami warning for neighbouring Southeast Asian nations.
There were no immediate reports of injuries, though the agency reported aftershocks of magnitude as high as 5, and Indonesia called tsunami warnings for areas in its provinces of North Maluku and North Sulawesi.
Regional governments in some cities, such as Ternate and Tidore, the former spice islands, were urged to prepare citizens for evacuation, while news channel Metro TV broadcast images of damaged buildings.
The quake, its magnitude revised down from an initial 7.8, struck at a depth of 35 km (22 miles), greater than the early figure of 10 km (6 miles), the USGS added.
Its epicentre was about 120 km (75 miles) from Ternate, in North Maluku, which has a population of more than 200,000, the agency said.
Hazardous tsunamis were possible along the coasts of Indonesia, the Philippines and Malaysia within 1,000 km (620 miles) of the epicentre, US tsunami warning authorities said.
Waves of height ranging from 0.3 m to 1 m (0.98 ft to 3.28 ft) above the tide level could hit some coastal areas of Indonesia, the Pacific Tsunami Warning Centre said.
It also warned of the risk of waves less than 0.3 m (1 ft) over tide levels for the coasts of Guam, Japan, Malaysia, Papua New Guinea, the Philippines and Taiwan.
Japan may see waves of up to 0.2 m (8 inches), but no damage is expected, the Japan Meteorological Agency said, as it warned a tsunami could occur in the Pacific.
Indonesia straddles the so-called Pacific Ring of Fire, an area of high seismic activity where tectonic plates meet and earthquakes are frequent.

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