Players and coaches for the Golden State Warriors and Boston Celtics as well as the U.S. men's soccer team on Sunday urged congress to support stricter gun laws amid a surge in mass shootings in the United States.

A shooting in Philadelphia left at least three people dead and 11 others wounded, police said on Sunday in the latest case of gun violence in the United States following recent massacres in Texas, New York and Oklahoma in which dozens died.

Ahead of Game 2 of the NBA Finals in San Francisco, players and coaches wore orange T-shirts that said "End Gun Violence" on the front and a list of advocacy organizations working to address the issue on the back.