HOUSTON – Firefighters rescued four people from a small pileup on the Southwest Freeway overnight.

The crash happened near Weslayan at about 12:45 a.m. Thursday.

It appeared a small car slammed into the back of a slower moving Chevrolet Impala, setting off a chain reaction crash involving two other vehicles. One of the vehicles ended up getting hit three times.

HFD extricated four people trapped inside their cars. Three of them were taken to the hospital.

Houston police are investigating who was at-fault in the incident.

Photos: 4-car pileup on the Southwest Freeway