CARACAS, Venezuela - A police officer who stole a helicopter and fired on two Venezuelan government buildings appeared in public for the first time Thursday night, defying a nationwide manhunt by showing up at a protest in the capital.

Except in videos posted on the internet, Oscar Perez hadn't been seen since he shocked the nation June 27 by using a stolen helicopter to fire grenades and gunshots at the supreme court and interior ministry buildings. The government called it a "terrorist attack."

Perez spoke briefly to journalists at a Thursday night vigil to honour the more than 90 people killed during three months of demonstrations against Venezuela's government.

He urged Venezuelans to vote en masse Sunday in a symbolic referendum being organized by the opposition to oppose President Nicolas Maduro's plans to rewrite the constitution. Perez said the vote should mark the start of a sustained street campaign to force the embattled socialist leader from office.

"It's the zero hour," Perez said as several masked youths looked on from behind. "The true way to pay respects to those who've died is for this dictatorship to fall."

He screamed, "What does Venezuela want?" That drew shouts of "Freedom!" as he raised his fist and hopped on the back of a motorcycle that sped off into the night.

In several videos, Perez has declared that he belongs to an uprising of members of the security forces who are fed up with Maduro's administration. Even though he had vowed to appear at an opposition rally, many people believed he had fled Venezuela following a nationwide manhunt in which the stolen helicopter was located near the Caribbean coast outside Caracas.

So far there has been no evidence backing Perez's claim that an uprising is underway among security forces even though Maduro frequently warns that the opposition is trying to woo the military into a U.S.-backed conspiracy to oust him from power.

Perez's colorful past has mesmerized Venezuelans. A trained pilot, he starred in a 2015 film, "Suspended Death," and his Instagram account is full of photos showing him in fatigues, bearing assault rifles, skydiving and standing in action poses with a German shepherd by his side.

His appearance at the rally came as a few hundred people braved steady rainfall Thursday night for a march in which they stopped at several spots in eastern Caracas where young protesters have been killed during the recent unrest.