A powerful earthquake struck off the coast of Indonesia, triggering a tsunami watch for countries across the Indian Ocean. The magnitude 8.7 quake was centered 20 miles beneath the ocean floor around 269 miles from Aceh's provincial capital.

The tremor was so powerful it was felt in Singapore, Thailand, Bangladesh, Malaysia, and India.

Workers at the Hermes Palace Hotel in Banda Aceh described a scene of panic, near the coast, as people fled to higher ground. Employee Cut Arlista said the shaking was so strong, water from the hotel pool spilled out, though the 70 guests at the hotel were not evacuated

"People were crying, and everybody was running inland as fast as they can," Arlista told ABC News.

The latest quake struck off the west coast of Sumatra, the same region devastated by a magnitude 9.1 earthquake in December 2004. That tremor triggered a catastrophic tsunami in the Indian Ocean that killed 230,000 people.

"I think a lot of people learned from the past," Arlista said. "Everybody knew to run as soon as the earthquake hit."