Police said Monday that a 鈥渟uspect vehicle鈥� has been identified in connection with incendiary devices that set fires to ballot drop boxes in Oregon and Washington state.

Surveillance images captured a Volvo stopping at a drop box in Portland, Oregon, just before security personnel nearby discovered a fire inside the box on Monday, Portland Police Bureau spokesman Mike Benner told a news conference.

That fire damaged three ballots inside, while officials say a fire at a drop box in nearby Vancouver, Washington, early Monday destroyed hundreds of ballots. The devices were attached to the outside of the boxes, police said.

Authorities said at a news conference in Portland that enough material from the incendiary devices was recovered to show that the two fires Monday were connected 鈥� and that they were also connected to an Oct. 8 incident, when an incendiary device was placed at a different ballot drop box in Vancouver.

鈥淗eartbreaking,鈥� said Greg Kimsey, the longtime elected auditor in Clark County, Washington, which includes Vancouver. 鈥淚t鈥檚 a direct attack on democracy.鈥�

The ballot drop boxes in Washington and Oregon both have fire suppression systems that are designed to activate when the temperature inside reaches a certain point, coating ballots inside with a fire-suppressing powder.

The system appeared to have worked in the Portland drop box, and security staffers were nearby to help put out the fire. Multnomah County Elections Director Tim Scott said the county has contracted with private security officers to have 鈥渞oving patrols鈥� that drive around the county 24 hours a day and 鈥減ut eyes鈥� on all drop boxes.

He said one of the guards was at the county elections office, heard what sounded like a blast 鈥� likely the activation of the fire suppression system 鈥� and called police.

For unknown reasons, the system failed to prevent the destruction of hundreds of ballots in Vancouver, just across the Columbia River from Portland.

Vancouver is the biggest city in Washington鈥檚 3rd Congressional District, the site of what is expected to be in the country, between first-term Democratic Rep. Marie Gluesenkamp Perez and Republican challenger Joe Kent.

鈥淚 hope the perpetrator of this reprehensible act is quickly apprehended 鈥� and local and federal law enforcement have my full support in working to keep our democratic process safe and secure,鈥� Gluesenkamp Perez said in a statement.

She said she鈥檚 requesting an overnight law enforcement presence posted at all ballot drop boxes in Clark County through Election Day.

鈥淪outhwest Washington cannot risk a single vote being lost to arson and political violence,鈥� her statement said.

Representatives for Kent鈥檚 campaign didn鈥檛 immediately return phone and email messages seeking comment.

The Portland Police Bureau said the fire there was reported at about 3:30 a.m. Multnomah County elections said only three ballots there were damaged, and the office planned to contact those voters to help them obtain replacement ballots.

A few hours later, television crews in Vancouver captured footage of smoke pouring out of a ballot box at a transit center.

There were surveillance cameras that covered the drop box and surrounding area, Kimsey said.

The last ballot pickup at the transit center drop box was at 11 a.m. Saturday, Kimsey said. Anyone who dropped their ballot there after that was urged to contact the auditor鈥檚 office to obtain a new one.

The office will be increasing how frequently it collects ballots, Kimsey said, and changing collection times to the evening, to keep the ballot boxes from remaining full of ballots overnight when similar crimes are considered more likely to occur.

An incendiary device was also found on or near a ballot drop box in downtown Vancouver early on Oct. 8. It did not damage the box or destroy any ballots, police said.

In a statement, the FBI said it is coordinating with federal, state and local partners to actively investigate the two incidents. Anyone with information is asked to contact the nearest FBI office, provide information through or call 1-800-CALL-FBI ( 800-225-5324 ).

Washington Secretary of State Steve Hobbs said the state would not tolerate threats or acts of violence meant to derail voting.

鈥淚 strongly denounce any acts of terror that aim to disrupt lawful and fair elections in Washington state,鈥� he said.

Voters were encouraged to check their ballot status online at to track its return status. If a returned ballot is not marked as 鈥渞eceived,鈥� voters can print a replacement ballot or visit their local elections department for a replacement, the Secretary of State鈥檚 office said.

Washington and Oregon are both vote-by-mail states. Registered voters receive their ballots in the mail a few weeks before elections and then return them by mail or by placing them in ballot drop boxes.

In Phoenix last week, officials said roughly five ballots were destroyed and others damaged when a fire was set in a drop box at a U.S. Postal Service station there.