Two Venezuelan government buildings were under fire by a stolen police helicopter for two hours on Tuesday.

Four grenades were launched from the helicopter - two at the Supreme Court building and two aimed at the members of the National Guard protecting the building, CNN reported. One of the grenades did not explode.

The helicopter fired 15 shots at the Interior Ministry while occupants inside hosted a reception for National Journalist's Day. No one was injured in either attack.

Venezuelan President Nicolas Maduro classified the attacks as a coup attempt carried out by "terrorists."

"We are going to capture the helicopter and those behind this armed terrorist attack against the institutions of the country," Maduro said.

Perpetrator

Officials believe the attack was led by police pilot Oscar Perez, a member of an opposition group. The group is compromised of military, police, and civilians, NBC reported.

Perez was opposed to Venezuela's "criminal government" and the "tyranny" of Maduro. He is on the run and wanted by the Venezuelan government.

One of the individuals in the helicopter was seen holding a banner which read, "Article 350 Libertad." Article 350 refers to the constitutional article which allows citizens to oppose the government when it acts undemocratically, CNN reported.

Civic Unrest

The attacks on government buildings appear to be the climax of clashes with the Venezuelan government.

Anti-government protests have been staged in Venezuela for the past three months.

Some protesters want Maduro to step down.

Maduro has responded to the protests by sending in the National Guard. At least 75 civilians have died in clashes with the National Guard, CNN reported.

Just this week, stores were looted on Monday and National Guard members prevented lawmakers from entering the National Assembly Tuesday prior to the attack, NBC said.

Oil is the backbone of the Venezuelan economy, and falling oil prices have driven Venezuela into a recession with hyperinflation.

Maduro is criticized for the economic state of Venezuela and for the food and supply shortages across the country. Hospitals are running low on basic sanitation supplies, including gloves, NBC reported.

Venezuela has an election on July 30 to vote for the National Electoral Council, Reuters reported. The Council, if approved, will be able to rewrite the constitution. Maduro's opponents are calling for early presidential elections instead of a vote for the Council.