DENVER (CBS) -- Denver police were seeking two suspects after four people were set on fire during an attack at a northwest Denver home.

Police spokesman Sonny Jackson says two men showed up at the front door of the residence at about 7:30 p.m. Thursday. Some words were exchanged, and a woman who answered the door was sprayed with a flammable liquid from a pump bug sprayer and set afire. Three other adults in the home also were sprayed with flammable liquid and set afire.

One victim suffered serious injuries and was transported to a local hospital, while the other three suffered minor injuries.

CBS Denver station KCNC-TV reports the liquid may have been gasoline and the attackers used a propane torch.

The woman who lives at the home told the station two men walked in and demanded drugs, threatening to set the home on fire. She said she believes they may have targeted the wrong home.

Jackson says the matter is under investigation and a motive had not yet been determined.

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