Armed, masked men have burst into a bar in Mexico and flung five human heads onto a crowded dance floor, in an apparent warning to a rival drug gang.
Mexican police have been fighting heavily-armed drugs gangs
An official said 20 men entered the bar in Uruapan city, Michoacan state, fired into the air, forced revellers to lie down and then "threw down five heads".
The men also left behind a note saying the act was "divine justice" carried out on behalf of "the family".
Michoacan state's Pacific coastline has become a haven for drug traffickers.
Magdalena Guzman, a spokeswoman for the state prosecutor's office, told the Associated Press news agency investigators believed the beheadings may be linked to drug smugglers.
"No one who was at the bar wants to talk because they are afraid," Ms Guzman said. "They were stunned."
The group of men, dressed in black and carrying rifles and handguns, burst into the bar shortly after midnight on Wednesday morning, officials said.
They fired into the air, ordered everyone to lie down and placed the heads on the floor.
A note they left behind said: "The family does not kill for money. It does not kill women or innocent people. Those who die are those who must die. Everyone should know that this is divine justice."
The victims have yet to be identified. Authorities have found 13 decapitated bodies in Michoacan this year.
Mexico's President-elect, Felipe Calderon, hails from Michoacan state and has vowed to curb drug violence.