An armed police officer stands guard outside the Stonewall Inn, Sunday, June 12, 2016, in New York. New Yorkers are gathering at the historic bar to grieve the deaths of at least 50 people in early Sunday's Florida gay nightclub shooting. The Manhattan bar became a national symbol of gay rights after a 1969 police raid led to violent street riots. (AP Photo/Mary Altaffer)
An armed police officer stands guard outside the Stonewall Inn, Sunday, June 12, 2016, in New York. New Yorkers are gathering at the historic bar to grieve the deaths of at least 50 people in early Sunday's Florida gay nightclub shooting. The Manhattan bar became a national symbol of gay rights after a 1969 police raid led to violent street riots. (AP Photo/Mary Altaffer) Credit: Mary Altaffer

Los Angeles — Amid heightened security in the aftermath of a shooting in Orlando, Fla., thousands poured into the streets of West Hollywood on Sunday for an L.A. Pride celebration charged with a new resolve.

Crowds converged on Santa Monica and Crescent Heights boulevards, waving rainbow flags, brandishing “We love Orlando” signs and chanting slogans. Cheerleaders in drag raising awareness for HIV readied their pompoms and a group of lesbian motorcyclists revved their engines.

“When our community comes under attack, what do we do?” some shouted, with others yelling the reply, “Stand up, fight back!”

City officials and civic leaders began the parade with a moment of silence and speeches calling for the celebration to serve as a rallying cry and a refutation to the violence at a gay nightclub in Florida, in which at least 50 were killed and 53 were injured early Sunday morning. The gunman was later killed in a shootout with police.

“This is a terrible reminder to the LGBT community that, though we’ve achieved so much in our fight for full equality, there is so much work to be done for love to prevail,” said West Hollywood Mayor Lauren Meister.

Los Angeles Mayor Eric Garcetti urged the marchers to celebrate and be proud in the face of violence.

“As Americans, we will not shrink away, we will not be stuck in our homes, we will not go back in our closets. We are out here to march, to celebrate and to mourn,” Garcetti said.

Gina Tedesco and her wife, Kim Kriegler, raised their fists as Garcetti spoke. The couple, married in September of last year, spent the morning joyfully preparing to ride in their first parade as a couple as part of the lesbian organization Dykes on Bikes. Then they turned on the news and heard about the nightclub shootings.

Like many at the parade, they swallowed their fears, donned rainbow bandanas and necklaces and walked out the door.

“Definitely had a thought that we’re a target,” Kriegler said. “But we’re going to keep going.”

Earlier Sunday, Santa Monica police arrested a heavily armed man in possession of explosive materials who told police he was looking for a friend at L.A. Pride.

Santa Monica police officials say they do not know what the suspect’s intentions were, but news of the arrest sent shockwaves through the gay, lesbian, bisexual and transgender communities participating in the parade.

The news about the arrest made Alonso Pina look over his shoulder a little more Sunday at the parade, which was his fourth time attending. But after what happened in Orlando, Pina said it never crossed his mind not to go.

“If something happens, it happened when I was showing my pride. I’m not concerned,” Pina said.

Lorenzo Mancillas, 51, of West Hollywood, stood quietly on Santa Monica Boulevard with a black sign with a rainbow border that just said “Orlando.” He usually doesn’t attend the parade because he doesn’t like crowds, but it was important to show solidarity today, he said.

“I’m somber. I’m happy, and I’m angry,” Mancillas said.

Authorities considered canceling the L.A. Pride parade after the arrest in Santa Monica but decided to continue with extra security, sources said.

For marchers such as Pina, it was a different kind of celebration. He usually greets marchers with a “Happy Pride!” but he hasn’t said it to anyone today.

“Because it’s not a happy pride. It’s a sad pride. It’s sad what we’re going through in this country.”