Outside a public library in Baldwin Park, Calif., the smoke streaming from the intentional fire set inside an official ballot collection box made the deposit slot look like a chimney. Firefighters first tried to pry the sides of the metal container open with a crowbar and an ax. After a few minutes, they pulled out a saw and began cutting through the frame.

As a sheet of metal finally fell away from the box, a thick cloud of smoke billowed out.

“We’re going to save as many ballots as we can,” a firefighter said in a live stream of the incident posted to Facebook Sunday night.

An unknown person dropped a flaming piece of newspaper into the ballot box outside the Los Angeles-area public library around 8 p.m. Sunday, officials said. Los Angeles County firefighters cut open the box and put the flames out, but dozens of cast ballots had already been damaged, either by the fire or the attempts to put it out. The city’s mayor estimated as many as 100 ballots had been affected by the vandalism.

After they quelled the flames, firefighters gathered the damaged ballots and delivered them to the Los Angeles County Registrar’s Office. County officials said voters who think their ballot may have been compromised can call the Registrar to find out if their ballot has been received. A Los Angeles County official told KCAL all of the damaged ballots have been accounted for and affected voters would receive replacement ballots in the mail.

Election officials asked local police, the FBI and the attorney general to investigate the incident as suspected arson.

“The arson of an official ballot drop box by the Baldwin Park Library in the First District has all the signs of an attempt to disenfranchise voters and call into question the security of our elections,” Los Angeles County Supervisor Hilda L. Solis said in a statement Monday. “Tampering, or attempts to tamper, with our democracy will not be tolerated."

Election officials had last collected ballots at 10:10 a.m. Saturday morning, the registrar’s office said in a statement Monday. Between the last ballot pickup and the fire, hundreds of people had dropped ballots in the box. Firefighters pulled handfuls of sopping wet and burned ballots from the ruined box Sunday night.

The incident is just the latest election hiccup in California, where ballot drop-off boxes have caused plenty of controversy in recent weeks.

Last week, unauthorized ballot boxes advertised by the California Republican Party sparked a standoff between the GOP and state officials who said the boxes were illegal and misleading to voters.

Republicans disagreed and doubled down, saying their organizers would not comply with state officials’ cease-and-desist order. The party said its boxes were legal because of a 2016 law that legalized ballot harvesting in California.

State officials “didn’t know the facts and didn’t bother to learn them before accusing us on Monday,” California GOP spokesman Hector Barajas said in a Friday statement. But California Secretary of State Alex Padilla (D) said the Republican Party was “saying one thing in the press and another through their attorneys.”

“They have agreed that they will not use the unstaffed, unsecured, ballot drop boxes that are misleadingly labeled to look official,” Padilla said in a statement. “Their public statements are simply meant to deflect from what they have to agreed to in writing.”

In Baldwin Park, some residents responded with dismay after one of the city’s two official ballot drop-off boxes was set on fire.

“People are frustrated across the country, it’s no different in Baldwin Park,” Mayor Manuel Lozano told KABC Monday. “The incident that happened … does send a very bad message.”

Resident George Silva said he was taking a bike ride through the park near the library when he saw smoke rising from the ballot box and filmed firefighters cutting it open on Sunday evening.

“Who would have an agenda to screw up an election?” he said in a video posted to his Facebook page. “All those voices aren’t going to get heard.”

Election officials reassured voters Monday, though, that they would do “everything possible” to make sure every legally cast vote is counted in November.

“The Los Angeles County Registrar will continue to do everything possible to ensure the integrity of local elections,” Los Angeles County Registrar-Recorder and County Clerk Dean C. Logan said in a statement. “Tampering with vote by mail drop boxes and ballots is serious criminal offense and we will vigorously seek the prosecution of individuals who engage in such behavior.”