Some 22 people have died in what Agence France-Presse has described as "three days of violence" in northern Mexico; authorities announced the new death count after they discovered five more bodies on Sunday in the country's state of Nuevo León, the newswire detailed.

The town government of San Pedro, a suburb of the industrial hub of Monterrey, said that the half-naked bodies of three individuals aged 18 to 30 were discovered in various city streets. A state investigator, who spoke to the newswire on condition of anonymity, detailed that each body had a head wound and that bullet shells found near the victims pointed to them having been killed elsewhere and then dumped on the street.

"They were executed," the unnamed official said. "It was a reprisal, without a doubt."

Two other bodies were found elsewhere around Monterrey, the state capital of more than 1 million inhabitants; all across Nuevo León, at least 17 other people were killed since Friday, AFP noted.

At least 10 of them had died when armed men attacked a beer distribution center on the outskirts of the capital, Mexican authorities said Friday, according to The Associated Press. The attackers invaded the property, demanded money from the workers and then started shooting, a state government official told the newswire; the source was also speaking on condition of anonymity given a lack of authorization to publicly discuss the incident.

Nuevo León State Attorney General Javier Flores told the AP that authorities are investigating the possibility that organized crime was behind the attack at the beer distribution center, where authorities found drugs and a weapon. National Autonomous University of Mexico security expert Raúl Benitez, meanwhile, warned that the violence could mean that the rival Zetas and Gulf cartels "are beginning to move their confrontation to Nuevo Leon," AFP noted.

But the killings might also be linked to power shifts following Mexico's June 7 midterm elections, Benitez suggested. Nuevo León was the scene of gruesome violence in the past, AFP noted; In the last two years, however, the state had lived in what the newswire dubbed "relative peace."