Oregon woman holds suspected arsonist at gunpoint as police warn residents against protecting properties

Video has emerged claiming to show an Oregon woman hold a suspected arsonist at gunpoint as police and Facebook move to strike down rumours of an Antifa conspiracy behind the state's wildfires.

It comes after police warned against armed groups confronting people in wildfire evacuation zones in an effort to protect properties from looters.

The video shared online purportedly shows the woman, Kat Cast, detain the man until police arrived at her home on Saturday, according to The Sun.

In the video, the woman can be seen detaining the man on the road as she asks him why he was going into her property with matches in his hand.

In sharing the video, she reportedly said she walked him out of her property at gunpoint and there was nothing fake about either the video or the person's attempt to ignite a fire.

"Some of you still think we're not being attacked," she said in a social media post, according to The Sun. "I found this individual walking in my property as I was driving in, all he had were some matches in his hand."

Facebook said on Saturday it would censor posts claiming the Oregon wildfires were started by certain groups, following confirmation from law enforcement that the rumours were forcing fire and police to divert resources.

It came after a Clackamas County Sheriff's deputy was placed on administrative leave for saying Antifa had been starting fires in his area.

"Antifa mother f***ers are out causing hell, and there’s a lot of lives at stake. And there’s a lot of people’s property at stake because these guys got some vendetta,” he says in the video.

Two days before that video, Clackamas County captain Jeff Smith told the county board of commissioners that they had "reliable sightings and reports" of Antifa in the area, according to Oregon Live.

“Equally concerning, is there are reports of people from other extremist groups — it’s not confirmed Antifa, but it’s suspected Antifa,” Mr Smith said. “Reports and sightings of people armed with chainsaws. And the goal was to fall telephone poles in hopes of starting further fires.”

Sheriff Craig Roberts said at a news conference on Monday that the information was believed to be credible at the time but had not been vetted through their sources.

“What we’re seeing in many of these cases is a friend of a friend of a friend said this,” Mr Roberts said, according to Oregon Public Broadcasting. “And when we get to the bottom of it, it is completely blown out of proportion.”