Several people were injured by a bomb in the Burmese city of Rangoon this morning, on the first anniversary of the military Government’s brutal crackdown against democracy demonstrators.

The explosion adds to the tension in the country’s biggest city, where convoys of armed police are patrolling in anticipation of the anniversary of the Saffron Revolution, when hundreds of thousands of Buddhist monks and ordinary Burmese marched against the junta.

Police told Burmese reporters at the scene that seven people suffered “minor injuries” from the bomb, which went off at 10.35 this morning next to Rangoon’s Mahbandoola Park. The victims appear to have been queuing at a bus stop, a few hundred yards from the place where soldiers opened fire on unarmed protesters on September 27, 2007.

One foreign witness, who was on the scene soon after the explosion, reported seeing at least three injured people, including two who lay motionless on the ground. The loud explosion rattled windows as far as two hundred yards away but caused little obvious physical damage. Within minutes the area around the explosion had been sealed off by police armed with rifles and guns for firing rubber bullets.

Police were to be seen probing the bushes and grass in the park, apparently in a search for further bombs, and photographing the site of the explosion. Plain-clothes intelligence agents moved people along and took the photographs of foreigners who lingered close to the scene.

“There was no bomb, no problem,” a plain-clothes security agent told The Times. “It is just a rehearsal – no problem.”

Small explosions are reported intermittently in Burma and, in the absence of any formal claim of responsibility, it is difficult to know for certain who is behind them. The Government blames them on “terrorists” from the political opposition or the ethnic armies, which are fighting long-running guerrilla wars on the country’s borders.

But the leader of the democracy movement, the Nobel Prize-winner Aung San Suu Kyi, has repeatedly spoken of her dedication to a non-violent struggle. Some Burmese speculate that the bombs are set off by agents of the Government to smear the opposition.

Two weeks ago two people died and ten were wounded by two explosions at a café in the northeast of the country, and last week three people were injured in an explosion on a Rangoon bus.

A year ago this evening, after a week of growing protests in several cities across Burma, the Government announced a curfew. Over the next three days at least 3,000 people were arrested and 31 killed, according to the United Nations, with more than 70 still missing.

Opposition activists say that there will be no street demonstrations this week, because of the intense security presence in Burma’s main cities. A convoy of ten trucks of riot police has been driving around the centre of Rangoon, with guns, truncheons, shields and bales of barbed wire on open display. Buddhist monks at monasteries that were involved in last year's disturbances report that plain-clothes spies are watching their comings and goings, and may even have infiltrated their ranks.

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