Updated

A man suspected of shooting his mother and killing three police officers called to the scene was found beheaded in southern Mexico on Tuesday, authorities said.

Fabian Ramirez's head was found at a highway intersection in Iguala, a town southwest of Mexico City, according to a statement from the Guerrero state Public Safety department.

A message was found nearby: "This is what happens to all those who kill a police officer or a soldier."

The department said Ramirez shot his 50-year-old mother in the back Monday, wounding her. He then allegedly killed three police officers who arrived at the scene, including Iguala's police chief.

Police captured Ramirez later that day, but four armed men broke into the jail and took him away by force.

An anonymous phone call led police to the head on Tuesday.

The four armed men were dressed in black and had lettering on their clothes identifying them as agents of Mexico's Federal Investigative Agency, the statement said. However, none of the police officers who had been guarding Ramirez recognized the four men, the department said.

Officials declined to say whether police were suspected in Ramirez' killing.

Beheadings have become common in Mexico's criminal underworld in recent years, most of them attributed to drug cartels trying to intimidate their rivals.

Nine men were found decapitated in Tijuana over the weekend. Six more people were found dead in the border city Tuesday, including a woman stuffed in a suitcase and a man found stabbed to death next to her. That brought Tijuana's homicide toll to 43 over four days.

Southern Guerrero state, home to the Pacific resorts of Acapulco and Zihuatanejo, has long been the focal of point of territorial fights between Mexico's drug cartels, land disputes and leftist rebellions.

The message found alongside Ramirez' head also included a threat against a powerful rancher and former mayor of the town of Petatlan who went into hiding in May after gunmen killed 17 of his associates and relatives.

The message was signed, "the people's avenger."