Police are searching for suspects after a shooting left one person dead and a man and his three children injured in a shooting near an apartment complex in Sunnyvale, Texas, Sunday evening.

Officers found one woman dead, a man injured by a gunshot wound, and the man's three children all with gunshot wounds, Sunnyvale police chief Bill Vegas said at a Monday morning news conference.

The man was released from the hospital Monday morning, according to Vegas, and his three children are still receiving medical treatment in Dallas, in stable but critical condition.

Sunnyvale is the easternmost city in Dallas County, around 16 miles from Dallas.

Vegas identified the woman found dead at the scene as Tyesha Merritt, 27, of Mesquite, Texas, a sister of the man who was shot.

The victims were sitting in a car outside the man's apartment when a suspect left their car, approached the victims' car, and opened fire, according to police.

He said the "best guess" investigators have about the car involved in the shooting is a "late model black sedan." Some witnesses said the vehicle had custom wheels, according to Vegas.

"We don't have anything really on our suspects," Vegas said, noting Sunnyvale and Mesquite police are working together to develop leads. "The suspect that exited the vehicle last night was masked up, so we can't see his identity at all. And aside from that, we really don't have a whole lot."

Vegas said police were "confident that the suspects have left Sunnyvale," but do not know whether the suspects and the victims knew each other.

Vegas urged any witnesses to contact police with information regarding the shooting.