MEXICO CITY (AP) -- Gunmen killed 15 people at a car wash today in a Mexican Pacific coast state where drug-gang violence has risen this year.

Officials say the gunmen in three vehicles drove up to the car wash in the city of Tepic and opened fire without provocation.

Fifteen men were killed and three people were injured.

The motive was not immediately clear but investigators suspect it was the work of organized crime.

In Ciudad Juarez, authorities say gunmen killed three undercover Mexican federal police officers as they waited for a person to cross a bridge from El Paso, Texas.

The Chihuahua state attorney general's office gave no further details of yesterday's shooting, but motorists crossing the Cordova Americas International Bridge were told by officials that there was a delay because of a shooting.

In an unrelated attack, a Chihuahua state police officer was killed today in his Ciudad Juarez home.

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