Seven injured, 3 of them with blood streaming from their heads.

Venezuelan pro-government militants wielding clubs and pipes stormed into the opposition-held National Assembly on Wednesday, attacking lawmakers and leaving seven hurt including three with blood streaming from their heads.

The special independence day legislative session turned into a violent, nine-hour siege when supporters of leftist President Nicolas Maduro then blocked the building and prevented 350 lawmakers, staff and others from leaving.

Police enable lawmakers to escape

Police initially did not intervene, but eventually joined soldiers to keep the mob at bay and allow the lawmakers to leave.

The attack is just the latest episode of political violence in three months of chaos in the oil-rich but poverty-stricken country that have seen 91 people killed in clashes with police.

Protesters blame Mr. Maduro for a desperate economic crisis that has caused shortages of food and medicine. The President has insisted that the chaos is a US-backed opposition conspiracy.

The unpopular Mr. Maduro, who condemned the violence, faces opposition demands for elections to remove him from office.

“I absolutely condemn these deeds. I will never be complicit in any act of violence,” Mr. Maduro said in a speech at a military parade in Caracas.

“I have ordered an investigation, and may justice be done.”

‘Losing our country’

Military police guarding the National Assembly stood by as about 100 intruders brandishing clubs and pipes, and one of them a gun, broke through the front gate in the late morning and into the interior gardens and then the building itself.

The mob streamed into the corridors of the congressional building, striking lawmakers, detonating stun grenades, and ordering journalists to leave the premises.

Lawmakers barricaded themselves inside rooms with furniture and rugs. When it was all over, there were blood stains on walls.

The opposition said seven lawmakers were injured and five needed to be hospitalized. Two National Assembly employees were also hurt.

“This does not hurt as much as seeing every day how we are losing our country,” lawmaker Armando Armas told reporters as he entered an ambulance with his head wrapped in bloodied bandages.

“Killers ... terrorists”

During the later siege, government backers gathered at the gates screamed “killers” and “terrorists” at the opposition lawmakers inside. At one point, lawmaker Williams Davila of the foreign affairs commission told reporters, “we have been kidnapped.”

Police with shields protected them as they finally filed out of the building.

The US State Department condemned the attack as “an assault on the democratic principles cherished by the men and women who struggled for Venezuela’s independence 206 years ago today.”

It also criticized Mr. Maduro’s “increasing authoritarianism.”

The Washington-based Organization of American States, Chile, and the regional Mercosur trade bloc also condemned the attack.

‘Dictatorship’

Earlier Vice President Tareck El Aissami made an unscheduled appearance at the National Assembly along with the head of the armed forces, Vladimir Padrino Lopez.

In a brief speech Mr. El Aissami said he was within a government branch that had been “hijacked by the same oligarchy that betrayed” independence hero Simon Bolivar.

He also called on Mr. Maduro’s supporters to come to the legislature to show support for the president.

A pro-government crowd rallied outside the building for several hours before breaking into the grounds during a recess.

“We will not be intimidated by these acts of violence. No one here will surrender to this dictatorship,” said senior opposition lawmaker Freddy Guevara.

‘Tipping point’

The government and opposition have accused each other of using armed groups to sow violence.

Mr. Maduro retains the public backing of the military high command — a key factor in keeping him in power, according to analysts — but the President last month said he was replacing four senior commanders of the armed forces.

Meanwhile, the action star helicopter pilot, who vanished after dropping grenades on the Supreme Court, reappeared in two online videos.

Oscar Perez, who is also an elite cop, called on the security forces Wednesday to turn on Mr. Maduro, who he said was at the Tiuna military base “with his henchmen and corrupt leadership,” and not the presidential palace.

Mr. Perez — who claims support from members of the military, police and public servants — urged Venezuelans in a Tuesday video to “stand firm” in their street protests.

On June 27, Mr. Perez and unidentified accomplices flew over Caracas in a police helicopter and dropped four grenades on the Supreme Court before opening fire on the interior ministry. There were no casualties.

Infuriating his opponents

Mr. Maduro has infuriated his opponents by launching a plan to form an assembly tasked with rewriting the constitution.

Opponents say he will pack this constituent assembly with allies in a bid to cling to power.

Voting for members of the assembly is scheduled for July 30.

“However, the political crisis is so fluid that the country could reach a tipping point before then,” Eurasia Group analysts wrote in a note last week.