A gunman opened fire at an off-campus college party in Texas, leaving two people dead and 14 injured before he escaped in the ensuing chaos, a sheriff said Sunday.

Authorities believe the shooter may have been targeting just one person at the party of about 750 people outside Greenville, 15 miles (24 kilometers) southwest of a satellite campus of the Texas A&M University System, and that others may have been shot at random, Hunt County Sheriff Randy Meeks said. Authorities had not yet identified the suspect and were still looking for him, Meeks said.

The shooting took place around midnight Saturday at what Meeks described as a Halloween and homecoming party for Texas A&M University-Commerce, though officials have said it was not a school-sanctioned event. Authorities believe there was one male shooter who entered the venue through the back door and began firing with a handgun, Meeks said.

Meeks described “complete chaos” after the shots rang out, with hundreds of people fleeing, including the gunman. The injured included four people who did not have gunshot wounds but who were hurt in the melee, he said.

The two people killed were both males, Meeks said, but he did not know if they were A&M-Commerce students. He said he believed four or five students may have been among those injured and estimated that most of the people at the party were in their late teens and early 20s. Some of the partygoers were wearing costumes, he said.

Authorities do not believe the gunman was wearing a mask or costume, Hunts County Sheriff’s Office Chief Deputy Buddy Oxford. He added that the shooter was dressed in a blue hoodie.

Authorities have not found the gun that was used, Oxford said.

The shooting came as Texas A&M University-Commerce, about 60 miles (97 kilometers) northeast of Dallas, celebrated homecoming weekend. According to its website, it is the second-largest university in the Texas A&M University System.

Word of the violence spread online overnight, with many sharing on social media graphic video purported to show seriously wounded victims lying on the ground as crying and screaming could be heard in the background.

“I just briefly saw one that was a very graphic video,” Meeks said. “I don’t know that’s going to help anything at all.”

Meeks said the party was held at a facility called The Party Venue and that the owner was cooperating with authorities. The venue sits along a highway in a rural area some 2.5 miles (4 kilometers) from the Greenville city limits. Meeks said he was not aware of any surveillance video in the area.

Outside the venue Sunday, a few Halloween masks and other debris were strewn about. Pools of blood could be seen on the ground.

A patrol sergeant and deputy were at the venue when the shooting happened, having been called there for complaints about illegal parking, Meeks said. An off-duty Farmersville police officer was also there, working as security for the party.

Authorities were questioning someone who appeared to be intoxicated when they heard gunshots from the back of the building, Meeks said.

Meeks praised the patrol sergeant and deputy, saying the sergeant quickly determined that one of gunshot victims had life-threatening injuries and transported that person to a hospital, while the deputy triaged others until paramedics arrived.

Texas A&M University-Commerce was founded in 1889 and was known by several names, including East Texas State University, before joining the Texas A&M system in 1996. The university has around 6,000 undergraduate students and 4,000 graduate students.

(AP)