CORPUS CHRISTI, Texas - Officials with the Texas Department of Public Safety say the weekend crash that killed three Houston teens and injured another was caused by distracted driving due to use of a cell phone.

The crash happened near Corpus Christi on Sunday afternoon.

Around 2 p.m. four young women were traveling northbound on Highway 77 near CR 73 when their vehicle veered off to the left, according to Texas DPS. Witnesses said the driver of the 2013 Hyundai Elantra tried to regain control but over-corrected and drove into oncoming traffic, colliding with an 18-wheeler.

According to DPS, the driver was distracted as she used her cell phone's GPS to navigate her way back home to Houston after a spring break getaway on South Padre Island.

The two teenagers in the backseat of the Elantra were killed in the crash. Authorities have identified them as Jade Robinson, 17, and Brianna Robinson, 19. The two girls are said to be sisters, their mom's only children. Authorities said both of the deceased were wearing their seat belts at the time of the accident.

The driver of the vehicle was also wearing her seat belt and was transported in stable condition to Spohn Memorial Hospital in Corpus Christi.

Authorities said the fourth victim was taken to the hospital in critical condition. That victim later died overnight Sunday into Monday morning. She was identified as 18-year-old Brittanie Tashay Johnson. The driver of the 18-wheeler was not injured in the accident.

Brittanie Johnson's friends and family held a candlelight vigil in honor of the accident victims Monday night. They released balloons in Brittanie's honor.

"I couldn't even believe it," said Traci Blount, Brittanie's mom. "I just kept being in denial thinking she's going to call, she's going to call, but it was real."

Brittanie's best friend Christopher Williams was just a few cars behind the girls when the accident happened.

"All you see and hear is that boom," Williams said."And you're like, 'Who is that?' I saw them pulling the bodies out, and I thought it can't be them. It's just unreal. Then I couldn't drive anymore because I knew it was them."

Grief continued to grip two families Monday night. Dozens gathered to light candles and mourn three beautiful women taken far too soon.

"I ask that you keep praying," Johnson said. "We're going to need your prayers after the funeral, two weeks after, a month after, we're still going to need those voices telling us it's going to be okay."

Video: Bellaire High School mourning loss of student

Brittanie's sister, Jazmyn Johnson, described Brittanie as "shy, sensitive, confident, outgoing."

Jazmyn had a message for all drivers. "Stay off the phone. It's dangerous," she said.

Family members say Jade Robinson, who attended Bellaire High School, had recently signed to play college volleyball in Tennessee.

Video: Distracted driving blamed for deadly crash

“I keep waiting for the door to open, for them to come back," mom Stacey Robinson told KHOU 11 News on Monday. "It's not fair, it's not fair."

“I will miss, I will miss both of my daughters so much."