Venezuelan authorities say a police helicopter attacked the country’s interior ministry and supreme court on Tuesday, firing at the ministry before hurling grenades at the court. Venezuelan President Nicolas Maduro, facing calls to step down amid three months of violent protests and economic calamity, described the incident as a “terrorist attack” on state television. “It could’ve caused a tragedy with several dozen dead and injured,” Maduro said, adding that the grenades failed to detonate and no one was injured. Venezuelan Information Minister Ernesto Villegas said 15 shots were fired at the interior ministry while a reception with 80 guests was underway. The chopper then moved to the supreme court and threw four Israeli-made grenades of “Colombian origin,” he said. Reporters from the Associated Press confirmed that sounds resembling loud gunfire were heard near the Supreme Court in Caracas, though they could not verify further details. Authorities say an army officer seized the helicopter and attempted to stage a coup.