LONGVIEW, Wash. – A 3-year-old boy died after the trailer his family was living in caught fire Thursday night. The rest of his family survived, but his father is in critical condition.

At 11:24 p.m. a single Longview fire engine responded to the report of a trailer fire in an alley behind 963 17th Avenue. The dispatch center heard there may be a victim in the fire and called for a medic unit and additional fire trucks.

When the first fire engine arrived, crews said they were greeted “with a large, emotional crowd exclaiming that there was possibly a young child trapped in the trailer,” Longview’s police and fire department said in a press release.

Crews found the trailer fully engulfed in flames. A nearby SUV was also on fire. Crews knocked down some of the flames and tried to search for the victim. The boy was found dead during a second search.

The victim’s parents and 2-year-old sister escaped the fire. The victim's grandmother and a neighbor were injured trying to help rescue the family.

All of the survivors were taken to PeaceHealth St. Johns Medical Center in Longview. The father remains in critical condition, Longview officials said.

The family had been living in the trailer temporarily, officials said. The family told fire crews they were in the trailer when the fire started, and the mother woke to sounds of the father screaming. The trailer was already filled with thick, hot, black smoke.

The fire was near the door, blocking the family’s exit. Witnesses and family members said they tried to rescue the 3-year-old boy but were unable to do so.

The cause of the fire has not yet been determined.

The American Red Cross was helping the family find housing assistance.

According to the Washington State Fire Marshals Office, there were 54 fatalities from fires in 2016.

“The tragic fire serves as a reminder of the importance of working smoke alarms, and having an escape plan which included two ways out, even when occupying an RV,” Longview officials said.