Authorities are trying to identify the suspects who killed two people and injured 28 others after opening fire early Sunday morning on a large crowd attending a block party in Baltimore.

The mass shooting happened around 12:30 a.m. in the Brooklyn Homes neighborhood. Police officials said the event was not permitted.

At least 30 people were shot, and half of them were ages 15 to 17. Two people were killed in the shooting, including a 20-year-old woman and an 18-year-old boy.

Investigators believe there were at least two suspects who fired their weapons during the shooting because shell casings from multiple calibers were found at the scene.

More about the mass shooting investigation can be found here.