Police say two men went to an apartment in the 4300 block of Lipan Street around 6:30 p.m. Thursday and knocked on the door.
When someone inside opened the door, one of the suspects sprayed a chemical from a weed sprayer while the other suspect threw a lit match into the unit, according to police.
The woman was taken to the hospital with serious injuries. Three other people who were in the home were also hurt but their injuries are minor according to police.
Chantel Ramirez, a resident of the apartment who was not in the home at the time, said the two men sprayed gas on the victims and demanded items from the home.
"Someone came up to the house, sprayed gas all over everybody and lit them on fire. [The suspects were] talking about, where's this? Where's that? I want this. I want that," Ramirez said.
Police say the matter is under investigation and a motive had not yet been determined.
About 20 minutes prior, police and fire crews responded to a small fire inside a check cashing store during an attempted robbery at 32nd Street and Champa. That fire was also started using a weed sprayer. No one was injured.
Police say there are some obvious smililarities in the two crimes but have not confirmed that they are related.
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