Rainbow flags of all sizes waved on City Hall Plaza Monday, as a crowd of more than a thousand turned out for a vigil honoring the victims of Sunday’s shooting massacre at a gay club in Orlando that left 49 dead and 53 injured.

A group of young people held candles, some posed for pictures swathed in a multicolored banner, others held signs reading “Unite Against Hate.”

Mayor Marty Walsh said after Orlando supported Boston in the wake of the Boston Marathon bombings in 2013, it’s now the city’s turn to help.

“We will continue to stand in solidarity with them and we will help them in any way we can,” he said.


At sundown, Walsh said, the building would be bathed in rainbow-colored light.

The Rev. Laura Ruth Jarrett, pastor of Hope Central Church in Jamaica Plain, led a prayer before a minute-long moment of silence. She implored the crowd to take action to address hatred.

RELATED: Boston Pride adds security after Orlando attack

“We will do something next,” she said, to cheers. She added: “I beg us to claim and practice the joyful complexity that is the LGBTQ community’s great gift to our families, neighbors and city. For we know that love is love is love is love is love is love.”

The crowd then slowly made its way inside City Hall to sign a condolence book to be sent to Florida.

Among those in the near-silent line inside the building was Steve Rivers, a 40-year-old Florida native living in Boston, who choked up when asked what message he planned to write for his friends back home.

“I’m still racking my brain because I’ve been in that club so many times,” he said, referring to the nightclub Pulse, where the shooter opened fire early Sunday morning. “It might be a while before I can go out to clubs again. It’s awful to have that feeling, like I don’t want to go somewhere where I have always gone.”

Massachusetts Gov. Charlie Baker also attended the vigil. Baker, whose brother Alex is gay, condemned anti-LGBT hatred in a news conference on Monday.

“There’s no room for that here in the Commonwealth or anywhere in society,” he said. “ We should, of course, do all we can to resist that.”

Several other vigils were held in the city on Sunday — including oneon Boston Commonand another in Copley Square — and Boston Pride held simultaneous moments of silence at its Sunday afternoon block parties.

RELATED:LGBT communities come together after tragedy in Florida

Earlier, Walsh posted a picture on Twitter of a rainbow flag flapping in the wind on the side of City Hall.

"This one is for you, #Orlando," the mayor's official account tweeted. "With love and heavy hearts from #Boston. #LoveisLove"

Boston landmarks werelit up with rainbow colors Sunday, and officials said the tribute would continue in some places on Monday night.