The gunman who opened fire at an educational program in Des Moines, Iowa, has been identified as 18-year-old Preston Walls. He has been arrested and charged with two counts of first-degree murder, attempted murder, and criminal gang participation.

Police and fire personnel responded to 455 SW 5th Street just after 12.50 pm on Monday after receiving reports of a shooting. The responding officers found two students, aged 16 and 18, in very critical condition and performed CPR on them. They were then taken to a nearby hospital, where they succumbed to injuries. The identities of the victims have not been released.

Police said the shooting took place at Starts Right Here, an educational mentorship program for at-risk youth in Des Moines. The program’s founder, identified as William Holmes, was also seriously injured in the shooting and remained in the hospital.

Authorities believe the shooting originated from a dispute between opposing gangs.

“Walls, and both deceased victims, are known gang members, belonging to opposing gangs, and evidence indicates that these crimes were committed as a result of an ongoing gang dispute,” police said in a news release.

Who is Preston Walls?

Preston Walls walked into the common area of the building carrying a 9 mm handgun that had an extended ammunition magazine.

William Holmes attempted to escort Walls from the common area but was unsuccessful. Walls pulled away and opened fire at the two teenagers before shooting Holmes, who was standing near him.

Walls then fled the scene in a vehicle. When cops stopped the vehicle, the gunman fled the scene on foot. He was eventually traced and found a short time later.

The weapon used in the shooting was found nearby.

“The ammunition magazine in the handgun has a capacity of 31 rounds, and contained three,” the news release stated.

Walls was taken into custody without incident and charged with multiple offenses, including murder.

Police said the gunman cut off a court-ordered GPS ankle monitor a few minutes before the shooting.