Rhanni S. Davis, a 30-year-old Chicago man, has been charged with four counts of first-degree murder in connection with the fatal shooting of four passengers on a Chicago Transit Authority Blue Line train.

The victims, identified as Adrian Collins, 60, and Simeon Bihesi, 28, were sleeping on the train around 5:30 a.m. when they were shot. Two other victims, a male and a female, have not yet been identified.

Davis allegedly fled the scene after the shootings but was arrested on the CTA's Pink Line. Police reportedly recovered a gun during the arrest.

Surveillance video allegedly showed Davis walking through a train car and shooting three of the victims seated separately. The fourth victim was in a different car.

The CTA said in a statement that "this heinous and egregious act of violence should never have occurred, nonetheless on a public transit train.