An explosion near the Venezuelan president's palace in Caracas has blown out windows at the headquarters of his honour guard and nearby homes but caused no injuries.
No one claimed responsibility for the blast, but Interior Minister Lucas Rincon blamed a small group of radical opponents of leftist President Hugo Chavez he said were trying to destabilise the oil-rich country.
"The intention is to create fear and panic. ... I think they are opponents of the government," Rincon told reporters today without providing any details or proof. "The presidential installations suffered absolutely no damage."
The blast alarmed residents and soldiers guarding Miraflores palace, where Chavez was believed to be at the time. Rincon said an explosive device was thrown over a wall of the honour guard barracks parking lot near rows of armoured vehicles. But it was far from the president's offices, he said.
The explosion was the latest in a string of bomb blasts this year in the world's No. 5 oil exporter, which is caught up in bitter political conflict over the rule of leftist former army paratrooper Chavez. Most of the blasts have caused damage but no lives have been lost.
The populist president, who survived a coup last year, is battling a determined referendum campaign from opponents who say his self-styled "revolution" for the poor is driving the nation into economic ruin and Cuban-style communism.
Rincon dismissed suggestions that the government may have set off the explosion itself in an attempt to disrupt the opposition bid to oust Chavez through the ballot box.
Chavez cancelled a trip next week to the United States and the UN general assembly in New York because of security concerns, according to government officials. They gave no further details.
Two bombs exploded outside the Colombian consulate and a Spanish Embassy site in Caracas in February and another blast in April damaged a hotel building where government and opposition negotiators held talks over a popular referendum.
No one claimed responsibility for those attacks, but the government and opposition blamed each other.