At least 63 people were killed in a strong earthquake that struck Myanmar, state media said while a series of aftershocks have caused panic but only limited damage from Thailand to Laos.

The death toll from Thursday's 6.8 magnitude tremor was expected to rise slightly in Myanmar after more than 100 buildings were destroyed. Over 100 people were injured, according to state television.

The quake sparked panic, but no major damage, in other countries across Southeast Asia. This month's devastating Japan quake and tsunami have revived memories of the even more powerful 2004 Indonesia quake and tsunami which killed around 226,000 people.

An aftershock, an estimated magnitude of 5.5, rattled Thailand on Friday but caused limited damage, although residents living close to the epicentre were advised to leave their homes.

The initial quake shook the famous "Golden Triangle" region, where Myanmar, Thailand and Laos meet. It was felt in the capital cities of Thailand and Myanmar and as far away as Vietnam, where people in tall buildings were evacuated.

It was 6.2 miles (10 km) below the surface but caused only slight damage on the Thai side. The town of Tachilek in Myanmar was badly hit by Thursday's quake. People fled their homes and cracks were seen in the roads.

"We were extremely frightened to enter the house since there were several strong aftershocks," a teacher said by telephone. "Some people are haunted by what they saw on TV about the recent earthquake in Japan."

The Red Cross said a hospital in Tachilek had been damaged and trained local volunteers had been mobilised to provide relief and first aid.

Thursday's quake was centred 111 km north of Chiang Rai, Thailand's northernmost province and a sparsely populated, hilly area. It forms part of the Golden Triangle, a popular tourist destination and famous for the cultivation of illicit opium.

In Chiang Rai's main town, little damage was seen. The spires of several Buddhist pagodas were bent, some tiles were smashed and a few cracks were seen on the ground close to a hotel.

Fearing more aftershocks, people in the province's Mae Sai district, 60 km from the epicentre, had left their houses and were seen setting up makeshift shelters in open spaces.-Reuters