San Rafael lowered its flags to half-staff this week to recognize the deaths of 34 people in a recent spate of mass shootings across the country — and the city will keep its flags down until Congress passes sharper gun control legislation, the mayor said.

Mayor Gary Phillips said Thursday that the symbolic gesture represents his mounting frustration over a deadly problem that he is powerless to fix, and that those who can are refusing to address.

“Do I have to wait until someone in San Rafael, in our family, gets killed to take further action?” Phillips said. “I'm just tired of waiting.”

Phillips announced his intentions during a City Council meeting Monday. His order will be in effect until Sept. 16. If Congress has not made progress on gun reform by then, he said he will ask the City Council to take up the topic and decide whether to keep the flags lowered.

The mayor’s grievances followed a proclamation from President Trump to lower flags at federal facilities to half-staff until sunset Thursday, in honor of those who died in mass shootings last weekend in El Paso, Texas, and Dayton, Ohio. Those tragedies occurred less than a week after the deadly July 28 mass shooting at the Gilroy Garlic Festival.

Phillips would not specify what actions on gun reform legislation he would support in Congress. “I am not prescribing that action, as that is their job, but I am saying that to do nothing is not acceptable to San Rafael,” he said.

San Rafael, a city of 60,000 people in central Marin County, is not typically known for its political theatrics. But on Thursday, several residents of the city and nearby communities said they supported Phillips’ action.

Theresa Sinnott, who has lived in San Rafael for 39 years, said she hoped the lowered flags would send “a message to people of influence (and) politicians to let them know that gun control really needs to happen — there have been too many killings.”

Olga Ventura, 27, said the statement made by lowering the flags is especially important to people in the Latino community, many of whom have feared for their safety after the recent shootings, especially in El Paso and Gilroy. About a third of San Rafael residents are Latino.

“We are concerned about it,” said Ventura, who is from Novato but was shopping in San Rafael on Thursday. “On social media, my friends and people that I know are posting comments about what happened in Gilroy.”

She said she and other Latino friends believe that the gunman who shot and killed three people and injured 13 others at the garlic festival was specifically targeting Gilroy because of the city’s large Latino community. The attack in Gilroy is being investigated as an act of domestic terrorism.

San Rafael resident Jim Wintermute, 61, said he supports Phillips’ refusal to raise the American flags, but he’s not confident that the move will prompt substantive action out of Congress.

“There are so many thugs out there with guns, and they’re not going to turn them in,” Wintermute said. “I just don’t see how the government can get a hold of it, even if they want to.”

Phillips, who was outwardly calm but clearly exasperated when he spoke to reporters Thursday afternoon at City Hall, said his decision to keep the flags at half-mast was borne of repeated disappointment. “For me, it’s simple: I am completely fed up with Congress not taking action.”

“I’m not going to put the flags back up until I see action from Congress,” he said. “I think it’s way past time for them to get off their dime and do something about this matter. I don’t want to wait simply for four or five days, (then) put the flags back up.”

Frustration over the failure to pass new legislation is part of the complex nature of gun control in the United States, where laws vary from state to state. Buying and selling rapid-fire, high-capacity firearms — like the ones used in the Gilroy, El Paso and Dayton killings — is legal under federal law and the laws of many states.

But it is not legal in California, which has some of the most restrictive gun laws in the country. It was against the law for the Gilroy gunman to enter California with the semiautomatic rifle he bought in Nevada, but experts say enforcing that law is problematic.

Among California’s stronger gun control laws are an assault weapon ban; barred sales of ammunition magazines that carry more than 10 rounds; and required background checks on all gun sales, including private sales, which addresses a federal issue known as the “gun-show loophole.”

President Trump said Wednesday there is “great appetite for background checks,” but his past declarations of support for tougher gun control have failed to result in new laws. National Rifle Association president Wayne LaPierre told Trump that his supporters would oppose background checks, and Senate Majority Leader Mitch McConnell has refused to bring gun control legislation for a Senate vote.

Fairfax resident Harold Perez, 55, was shopping at Montecito Plaza on Thursday when he glanced at the American flag at half-staff in front of the San Rafael fire station across the street.

“I agree with that,” he said, noting that he supported the mayor’s action. Mass shootings, he said, “have been going on for a long time, and I think it’s time for more gun control.”

Lauren Hernández. Pete Grieve and Steve Rubenstein are San Francisco Chronicle staff writers. Email: lauren.hernandez@sfchronicle.com, pete.grieve@sfchronicle.com, srubenstein@sfchronicle.com Twitter: @pete_grieve, @LaurenPorFavor @SteveRubeSF