Two bodies were dumped on a highway popular with tourists for scenic views
Thirteen people have been killed in an outbreak of drug-related violence in the southern Mexican beach resort of Acapulco, officials have said.
Five of the dead were police officers whose patrol was machine gunned.
Eight other bullet-riddled bodies were discovered in different areas around the city - four had been beheaded.
Acapulco is one of Mexico's biggest tourist resorts, but in recent years it has been the scene of bloody turf wars between rival drug cartels.
In June, 18 people were killed in a shootout between drug gangs and soldiers in the city, which is home to about 600,000 people.
The Pacific states of Guerrero and neighbouring Michoacan are largely under the control of the powerful "La Familia" cartel.
President Felipe Calderon has deployed thousands of troops and police across Mexico in an attempt to combat drug-related violence, which has left more than 15,000 people dead in the past three years.
The latest bloodshed could not have come at a worse time: it is a holiday weekend in Mexico and the start of the spring break, which brings a surge of American visitors.
At least two of the decapitated victims were dumped close to the centre of Acapulco, on a highway popular with tourists for its scenic views.
The BBC's Julian Miglierini, in Mexico City, says the country's drugs war has cast a long shadow on the world-famous sunny beaches of the city known as Mexico's Pacific Jewel.
Although many Mexicans and foreigners continue to choose Acapulco as a holiday destination, Saturday's events seem to confirm that its reputation as an idyllic destination is long gone, he adds.