JOHNSON COUNTY, Texas (CBSDFW.COM) – Two 17-year-olds were killed in a single-vehicle crash Sunday afternoon in Johnson County, officials said.

The Texas Department of Public Safety said troopers responded to the crash just before 12:30 p.m. on CR 604 near Happy Trail Road.

Officials said a vehicle with a 39-year-old driver, identified as Barbara Underwood, and the two teenagers was traveling north on CR 604 when it approached a bridge.

For an unknown reason, the vehicle “veered to the left, just before the bridge” and crashed into the railing, officials said.

The two teenagers were pronounced dead at the scene while the driver was taken to the hospital with serious injuries.

Officials said the two teenagers were from Alvarado.

They were identified Monday as Hannah Underwood, 17 and Hayley Underwood, 17.

The investigation into the crash is ongoing.