13 people were wounded after at least two gunmen opened fire early at a Chicago house party early on Sunday morning, USA Today reports

Patrol Chief Fred Waller said authorities have arrested two people who are believed to be the shooters. One suspect was armed with a revolver while the other had suffered a gunshot wound during the incident. Waller claims that there were three separate shootings at the party stemming from one altercation. 

"There was a dispute where shots were fired inside," Waller said. "The people started to spill out, and as they spilled out more shots were fired. So we have about three [shooting] scenes."

Some of the shooting outside of the party was caught on police cameras by officers who were responding to the initial disturbance. The later shootings seem to have had no specific target, rather they were just firing at people who attended the event.  

"POD videos shows who was firing outside so we have some information about what happened there... It looked like they were just shooting randomly at people as they exited the party," Waller explained to the local ABC-affiliate. "One of the people who left the party also fired shots at a passing vehicle."

The party was to celebrate the life of someone who was killed in April.

The victims ranged in age from 16 to 48. Police think the shootings were caused by a personal dispute and was not gang-related. Mayor Lori Lightfoot visited victims at the hospital and is urging anyone with information on the incident to come forward. She also wants community leaders to rally behind victims of gun violence to help make the city safer. 

"People deserve to live their lives without fear of someone pulling out a gun," she said per USA Today. "Especially in a moment of reflection and remembrance during the holiday season."