JAKARTA, Indonesia - A 7.3-magnitude earthquake struck Sunday about 30 miles under the Molucca Sea in northeastern Indonesia, the US Geological Survey said.

Related readings: 4 killed in moderate quake near SumatraModerate quake hits Indonesia Powerful quake rattles western IndonesiaIndonesia quake triggers tsunami warningPrayers in Indonesia as looters hinder quake aid Aid flows in for Java quake victims Hopes wane for Indonesia quake survivorsIndonesia quake: Aid comes, deaths reach 5,136 Quake toll tops 5,000, aid pours inThousands spend 2nd night in open as quake toll passes 5,000

The epicenter of the major quake was about 80 miles from the city of Ternate, in north eastern Indonesia, it said. It had a depth of more than six miles below the ocean floor.

No tsunami warning was issued.

An official with the Pacific Tsunami Warning Center in Hawaii told The Associated Press that a basin-wide tsunami - one that travels a great distance or across an ocean - isn't expected, though a tsunami near the earthquake's site is "always possible."

"Given the size of the earthquake, we think a basin-wide tsunami isn't likely, though a local tsunami could be possible," said Brian Shiro, a geophysicist at the tsunami center.

Indonesia, the world's largest archipelago, is prone to seismic upheaval due to its location on the so-called Pacific "Ring of Fire," an arc of volcanos and fault lines encircling the Pacific Basin.

In December 2004, a massive earthquake struck off Indonesia's Sumatra island and triggered a tsunami that killed more than 230,000 lives - 131,000 people in Indonesia's Aceh province alone.

Ensuing Panics

"You could feel shaking up and down and to the left and right," a Reuters eyewitness said.

"People panicked and ran out of their homes. They are still outside their homes," he said about 30 minutes after the quake struck in the Molucca Sea about 165 km (100 miles) to the east of Manado near the northern tip of Sulawesi.

There were no immediate reports of casualties but local television said some buildings were cracked. Manado, a city of some 400,000 people, is 2,200 km (1,365 miles) northeast of Jakarta.

The U.S. Geological Survey Web site put the quake's magnitude at 7.3 while Indonesia's meteorology and geophysics agency gave its strength as 6.5 on the Richter scale and said it could pose a tsunami risk, according to a message from the agency received by Reuters.

The USGS said the quake had occurred at 7:27 p.m. (1127 GMT). It originally reported the magnitude at 7.2.