Police in Burma said Thursday they had arrested a man in connection with deadly blasts in a Rangoon park last month, blaming the attacks on a militant exile group opposed to the ruling junta.

A series of explosions on 15 April left 10 people dead and dozens wounded as thousands of people gathered for water-throwing festivities to mark the Buddhist New Year, in the worst attack in five years in Burma’s main city.

“This brutal act was committed by four terrorist murderers who are members of a group known as the Vigorous Burmese Student Warriors,” Burmese police chief Khin Yi said.

One suspect was arrested while the others fled across the Thai border, police announced at a news conference in the remote administrative capital Naypyidaw.

Police said that three grenades had been thrown into the crowds. Another device, made with a beer can filled with explosive powder and attached by detonation wire to a mobile telephone, failed to explode.

Members of a movement calling itself the Vigorous Burmese Student Warriors, armed with AK-47 assault rifles and grenades, stormed the Burmese embassy in Bangkok in 1999 and took 38 hostages.

Burma has been hit by several bomb blasts in recent years which the junta has blamed on armed exile groups or ethnic rebels.

The latest attacks came as the country prepares for polls planned for the end of this year, which critics have dismissed as a sham due to laws that effectively bar opposition leader Aung San Suu Kyi from participating.

Suu Kyi’s party, the National League for Democracy (NLD), was set to be dissolved at midnight Thursday under laws laid down ahead of the elections.

The NLD refused to meet a 6 May deadline to re-register as a political party, which would have forced it to expel its own leader, and boycotted the vote scheduled for later this year.

The military has ruled Burma since 1962, partly justifying its grip on power by the need to fend off ethnic rebellions that have plagued remote border areas for decades.

In May 2005, blasts at two Rangoon supermarkets and a convention centre killed 23 people. The junta blamed those explosions on exile groups.

Armed minorities in Karen and Shan states continue to fight the government along the country’s eastern border, alleging they are victims of neglect and mistreatment.

In other recent attacks, a series of bomb blasts hit a controversial dam project in remote Kachin state last month, while a series of grenades exploded at a hydropower project in Bago Division.

In eastern Karenni state, a man being interrogated by police was reported to have detonated a bomb last month, killing himself and wounding four officers.

Burma’s police chief said in August last year that security forces had foiled a plot by a man sent by exiled pro-democracy groups to bomb Rangoon during a visit by UN secretary general Ban Ki-moon the previous month.

Rights group Amnesty International in February called on the regime to end repression of ethnic minority groups ahead of the vote, accusing the regime of arresting, jailing, torturing and killing minority activists to crush dissent.