Arson destroyed the Venezuelan Embassy and damaged offices used by the Organization of American States in St. Kitts and Nevis in what the prime minister of the small Caribbean nation said Monday was a politically motivated attack.

Both fires at the buildings in Bassettere, on the island of St. Kitts, occurred in the pre-dawn darkness of Sunday. Authorities responded to the fire at the OAS offices around midnight, and were called out to the nearby embassy several hours later.

The Venezuelan Embassy was reduced to charred rubble while the OAS office sustained only minor damage. No one was injured in either fire.

Police Inspector Lyndon David said two men, whose names were not released, were in custody but had not been charged. He said there was no evidence to suggest a motive.

But Prime Minister Denzil Douglas said the fires occurred after a political demonstration by allies of the opposition Unity Party and he blamed them for what he called "extreme political tactics" aimed at destabilizing the government.

"There are those in this country whose primary objective is to win as they define winning regardless of the impact on our proud, progressive nation," he said in nationally broadcast address in the two-island country. "They are energized more by what they are determined to destroy than by what they wish to build."

Mark Brantley, the leader of the opposition in parliament, condemned the attacks and urged the public to help police resolve the case. He said he called the Venezuelan ambassador and OAS representative to express his "sorrow and revulsion" over the incident.

"We find especially abhorrent any attack on the personnel or property of friendly foreign nations, which have all provided and continue to provide invaluable support," Brantley said.

Politics in the islands have been increasingly polarized since December, when Brantley filed a no-confidence motion aimed at forcing elections. The majority has not allowed a vote on the motion. In October, Unity led a march that filled the streets of Basseterre with hundreds of demonstrators, a large turnout in a small nation of about 50,000 people.

Douglas said the country should not allow the political rift to undermine security. "I call on all nationals, regardless of political persuasion, to condemn these acts in the strongest possible terms," he said.