A football game in Mexico's top league ended early after gunmen opened fire on police outside the stadium in the northern city of Torreon.
The shooting caused panic inside the stadium, where Santos was playing Morelia, and players ran for cover.
Hundreds of fans then ran onto the field to move away from the sound of the gunfire outside the stadium.
One police officer was wounded in the incident, but no one inside the stadium was hurt.
compiled from agency reports