One person was killed and six people were wounded Sunday evening in a mass shooting during a party in a Rochester, N.Y., park, authorities said.

Multiple police jurisdictions responded to the incident at Maplewood Park, and a 20 year-old person was declared dead. At least one of the other six victims was listed in critical condition, police said.

“At this point we don’t know how many people were shooting. We are trying to work our way through that. We are trying to work our way through as many witnesses as we can,” Rochester Police Capt. Greg Bello told Rochester First.

Some of the victims were transported in private cars, even as ambulances arrived. 

Police say they responded to the park on about 6:20 p.m. for a report of a large gathering with shots fired and found several people wounded and others fleeing the scene.