CIUDAD JUAREZ, Mexico (AP) -- Two gunmen burst into a home east of the Mexican border city of Ciudad Juarez where people were celebrating a baseball victory and killed 10 people, authorities said Monday.
The killings occurred Sunday night in Loma Blanca, a town in the Juarez Valley. The dead included a 7-year-old girl, her mother, three teenage boys and five adult men, said Arturo Sandoval, spokesman for the Chihuahua state prosecutors' office.
The bodies were found scattered over a radius of about 12 yards (meters) around the home, suggesting some had tried to flee when they were gunned down. A trophy from the baseball game was also found at the home.
The manager of the local baseball team, the Cardinals, was present at the party and said a total of about 30 people attended, but the others were able to escape by running away. He said he saw only one gunman, who he described as a young man.
The manager, who asked not to be identified by name for fear of reprisals, said the killings could have been motivated by resentment over the team's victory; he said there is betting on games in the local league.
Over 30 shell casing found at the scene indicated that an assault rifle was used in the attack.
"One of the lines of investigation it's a possible revenge," said Jorge Gonzalez Nicolas, an assistant Chihuahua state prosecutor. He said five men were kidnapped from the town's baseball field two months ago, and the killings could be related to that.
He said witness statements cast doubt on a possible drug gang link. He added that at least two gunmen took part in the assault.
Chihuahua Gov. Cesar Duarte said "there is evidence that we will make public soon" in the case, which he said "will not stop us in the battle against impunity."
It was one of the biggest massacres in the area since the 2010 killing of 15 people in an attack on a birthday party in Villas de Salvarcar, a working-class neighborhood of Ciudad Juarez, across the border from El Paso, Texas.
Sandoval said there was no information yet on the possible motive in the Loma Blanca killings; The Villas de Salvarcar massacre was believed to have involved a case of mistaken identity, in which one drug gang attacked a party it mistakenly thought was attended by members of a rival gang.
The Juarez Valley, a largely agricultural region that stretches along the Rio Grande, has been the scene of frequent turf battles between gangs allied with the Sinaloa drug cartel, and gunmen of the local Juarez cartel.
However, violence in Ciudad Juarez and surrounding areas has dropped significantly in recent years.
Ciudad Juarez recorded 341 homicides so far in 2013, down from 952 killings by gangs in the first half of 2012, and 1,642 in the first half of 2011.
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