A strong undersea earthquake hit North Maluku province in eastern Indonesia on Thursday, triggering panic among frightened residents and a brief tsunami warning.

There were no immediate reports of damage or casualties after the quake, which the U.S. Geological Survey put at magnitude 6.7 and the epicentre at a depth of 45 km (28 miles).

The agency had initially put the quake at magnitude 7.4 and a depth of 88 km.

"We have lifted the warning. After monitoring, there were no signs of tsunami," Fauzi, the head of the seismology centre in Indonesia's meteorology agency, told Reuters.

The Pacific Tsunami Warning Centre also said on its Web site that it did not expect a "destructive Pacific-wide" tsunami but said quakes of this magnitude can sometimes create local tsunamis.

The quake struck at 2.40 pm (6:40 a.m. British time), with the epicentre 234 km northwest of the provincial capital Ternate, both agencies said.

People on the ground said the quake sparked panic.

"It was felt for about 15 seconds and the students ran out of classrooms in panic," Arifin, a school teacher in Ternate, said by telephone.

Stevanus Ngenget, a lecturer at De La Salle University in Manado, the capital of neighbouring North Sulawesi province, also said there was panic at his campus.

"I saw a lot of people went out from the classroom and gathered in the hall. They cried out, 'quake!' but I myself did not feel it," he said.

Indonesia suffers frequent earthquakes. The island chain lies along the so-called "Pacific Ring of Fire", where several tectonic plates collide.

Earlier on Thursday, a moderate undersea quake jolted Indonesia's Aceh province, but there were no reports of any casualties or damage, the Meteorological and Geophysics agency said.

In December 2004, a massive undersea quake and tsunami hit Aceh on the northern tip of Sumatra island, leaving as many as 170,000 dead or missing in that province. Many thousands more were killed in other Indian Ocean nations.