suspected drug hitmen killed the mayor of a town outside Mexico's northern business city of Monterrey

7 people were killed in a drug gangs shootout in Mexican resort city of Acapulco, according to local authorities.

The Associated Press reports that Guerrero state investigative police director Fernando Monreal said gunmen used grenades and automatic rifles to attack a house in a residential area of Acapulco on Thursday.

The state of Guerrero, where Acapulco is located, has become a drug cartel battleground.

Mexican police source also said that suspected drug hitmen killed the mayor of a town outside Mexico's northern business city of Monterrey Thursday. He was the fourth public official slain in little over a month.