TITUSVILLE, Fla. -- Sunday night, family and friends were struggling to come to terms with the tragic crash that killed 2 Titusville teens.

Morgan Gordon, 16, and Chelsea Beck, 17, were killed when Gordon lost control of an SUV on State Road 405. The vehicle flipped and rolled several times before landing upside down in a water-filled ditch. Police said the teens had been drinking. They believed the girls had just left a party in Port St. John.

Both girls were students at Astronaut High School. Gordon was a cheerleader, and squad members said her death is hard on the team.

"She was part of the cheerleading squad. When you're part of the squad, you're part of the family, " said classmate Shilo Dayhoff. "It's just sad because you don't think that something like that is going to happen to one of your friends. Especially Chelsea. She's in my 3rd period class and when I go to school I'm going to be looking at an empty desk sitting in the next row."

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Another friend of the victims told Channel 9 Eyewitness News the girls were well known in the school. Jessi Smith said, "A lot of people know Morgan and Chelsea are very friendly, very popular girls. They were everyone's friends."

Sunday afternoon, flowers and memorials had been left at the crash site in memory of the girls. Grief counselors were expected to attend the high school on Monday to talk with students.

Investigators said the crash took place along a stretch of State Road 405 where the speed limit was 45 miles per hour. Authorities believed the SUV was going at least 70 miles per hour when it lost control.

Police are now looking for the person or people who gave the alcohol to the girls. They said they had several strong leads and hoped to make an arrest soon.