The bodies of six men who had their throats cut were recovered outside the same central Mexican city where gunmen tossed five severed human heads onto a bar dance floor, authorities said Saturday.

Investigators said the victims were discovered Friday, buried in a hole next to a highway near the Indian community of Angahuan, outside the town of Uruapan, in the Pacific Coast state of Michoacan.

The gruesome discovery came just two days after gunmen burst into a bar on Uruapan's outskirts and threw the heads on the dance floor. The heavily armed men fired their guns in the air as they entered the bar.

CountryWatch: Mexico

The attackers left a note written on a piece of cardboard reading: "The family doesn't kill for money. It doesn't kill women. It doesn't kill innocent people, only those who deserve to die."

Investigators said the beheadings likely were linked to organized crime or drug smuggling, though no arrests have been made.

Michoacan is thought to be a base for powerful cocaine, marijuana and methamphetamine smugglers with ties to some of Mexico's largest and most-violent drug cartels.

Arrests of major Mexican kingpins in recent years have sparked an increasingly brutal and ruthless drug war in different parts of the country as gangs battle for control of lucrative smuggling routes into the United States.

So far this year, at least six heads belonging to police and rival drug smugglers have been found in the Pacific resort of Acapulco. One washed up on a popular beach in the tourist zone, and the rest have been dumped in front of government offices.

In the past few months, severed heads also have been found in other states plagued by drug violence, including the border states of Baja California and Nuevo Leon.

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