Yangon: A small explosion took place in front of a luxury hotel Friday evening in the Myanmar capital Yangon, but there appeared to be no casualties, witnesses said.

The explosion took place at about 6:45 p.m. local time, according to the staff of the Traders Hotel, who said no one was hurt.

Several street vendors nearby said the explosion appeared to have originated next to a signboard on a small lawn next to the hotel, and that there appeared to be no casualties.

They were uncertain of what caused the explosion. Hotel staff and witnesses both asked not to be named, not wishing to attract the attention of the authorities, who severely restrict the flow of public information in the military-ruled nation.

Security forces, including armed soldiers, sealed off the area along Sule Pagoda Road, one of Yangon’s busiest thoroughfares, and were inspecting the site. No officials were available to speak to journalists, who were kept at a distance from the scene.

In recent years, the tightly-guarded Myanmar capital has been rocked by a number of bombings for which no group has claimed responsibility.

The government has blamed exile dissident groups opposed to military rule. In the absence of convincing evidence, however, there has also been speculation that the bombings are provocations by the authorities themselves, or part of an internal struggle with the ruling circles.

In the most serious attacks, on May 7 this year, at least 23 persons were killed and more than 160 others injured when bombs exploded at two supermarkets and a convention center in the capital.

The junta came to power in 1988 when it crushed a pro-democracy uprising led by Nobel Peace Prize laureate Aung San Suu Kyi. It held elections in 1990 but refused to hand over power when Suu Kyi’s party won an overwhelming victory.

In addition to the legal political opposition of Suu Kyi’s National League for Democracy party, the junta numbers several ethnic guerrilla groups along the country’s border among its foes, in addition to many groups of exiles, most notably former students.

Friday night’s blast was felt and heard by people living in the area, but no shattered glass could be seen at a distance.

“The explosion was loud and I could feel the building shudder,” said Myo Myo, a woman who was eating dinner at the nearby Grand Miyahta Hotel.

Despite the absence of free and timely media reports, news of the blast spread very quickly among residents of the capital, still jittery from the bombings earlier this year.

An Asian diplomat said the explosion heightened security concerns in the diplomatic community, already disturbed by the withdrawal earlier this month of armed police posted outside the residences of foreign envoys, to be replaced by plainclothes personnel. He spoke on condition of anonymity so his comments would not be seen as breach of diplomatic protocol.