An armed attacker shot several people Tuesday in the Azusa community of Los Angeles County, killing one, scattering would-be voters, and forcing a lock-down of two polling sites before dying of a gunshot wound.

It was not clear if the shot was self-inflicted or came from police.

Three people were hurt in the incident, which included a standoff with authorities. No other information was available about the motive for the assault.

“It’s too early to know about motive," said Azusa Police Chief Steve Hunt during a press conference.

The incident did not appear to have any connection to the polling locations, the Los Angeles County Sheriff's Department said in a statement Tuesday evening.

Azusa police tweeted that, as of 8 p.m. ET, the "Situation has transitioned from active to barricade/containment . . . All those near scene shelter in place all others stay out of the area."

Los Angeles County Registrar-Recorder/County Clerk Dean Logan tweeted that voters should seek alternate polling places because the Tuesday afternoon shooting impacted two voting sites, including an elementary school.

The Azusa Police Department said shots were reported near the Memorial Park polling site, where voters were casting ballots, at about 2 p.m. The department said officers who responded to the scene discovered "multiple shooting victims," then were fired upon themselves. Some officers were "pinned down" by gunfire, and multiple officers exchanged shots with the shooter.

The shooting led to a lockdown for voters at both the Memorial Park North Recreation Center and nearby Dalton Elementary. School. Voters were urged to go to alternate polling sites to cast their ballots, but anyone who was already inside was trapped until the shooter was contained.

Francisco Vargas, 20, had just started to fill out his ballot.

“I was actually voting, when we heard the gun shots,” Vargas said. “Then we heard more shots, and my hand is shaking – still trying to vote.”

Vargas said poll workers peeked out the door of the voting site, spotting cops outside. The building was then put into lockdown, trapping at least 40 people and a dozen preschoolers inside. The children were being given a tour of the polling place when the shooting began.

Soon, the trapped voters could hear a swarm of sirens and helicopters. Many assumed the polling place was under attack, so they began calling their loved ones, “just in case they don’t speak to them again,” Vargas said. After about an hour inside the lockdown, the voters figured out that the polling place wasn’t directly involved in the shooting, and the fear began to dissipate.

Vargas said the crowd was evacuated at about 4:30 p.m. A SWAT team surrounded them and walked them out of the building in a single file line.

“It was just a really really intense first-time voting,” Vargas said. “A fitting end to a crazy presidential election.”

The police department has said all officers who were pinned down are "accounted for, safe and rescued."

In addition to the person who died, two more shooting victims were taken to a hospital in critical condition. One more victim was was "down near primary residence," according to the department, but no other details have been provided. The critical victims were airlifted to a nearby hospital, according to Los Angeles County Fire Inspector Gustavo Medina.

The registar’s office was awaiting details on the shooting, but spokeswoman Brenda Duran said it did not appear to have happened in or immediately near the polling place.

‚Äč“The only thing we know now is that places around there have been asked to be on lock-down,” Duran said.

Police also were asking residents to shelter in place after the incident. Both of the polling sites were on lockdown due to the shooting, KCBS and KCAL were reporting.

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