Trooper Cliff Pratt said men in two vehicles began flashing gang signs at each other as they both drove on SR 405 sometime before 5 p.m.
As the vehicles sped down the highway, shots rang out and two men from one of the vehicles were hit, Pratt said. Those men continued on to a Beacon Hill home before calling police.
The victims, ages 23- and 24-years old, were taken to Harborview Medical Center with non life-threatening injuries, according to Seattle Fire Department officials.
The shooters got away, and police are now looking for a black Cadillac Escalade.
WSP and Tukwila police are leading the investigation.