Mutilated bodies found in Acapulco

The victims, all male, were discovered at dawn near a shopping mall along with several threatening hand-written messages that are typically left as a calling card by drug cartels, authorities said.

The messages were signed by Mexico's most wanted man Joaquin "Shorty" Guzman, the leader of the powerful Sinaloa cartel that is fighting rivals over the area, police added.

"This is a war that has been growing for months, not just in Guerrero but across the country," said Guerrero state government spokesman Manuel Nava. "We are witnessing the break-up of these organized crime gangs," he told Mexico's Foro TV channel.

The half-naked bodies were mutilated and badly beaten, and machetes appeared to have been used, police said.

The Sinaloa gang is waging a brutal war for control of Acapulco, its port and routes toward the United States, fighting the weakened Beltran Leyva cartel and the South Pacific cartel, a breakaway faction of the Beltran Leyva gang.

The gangs are spreading fear in Acapulco, damaging the vital tourism industry, although business owners are desperate to assure visitors that their city is safe for tourists.

A burned-out truck and four other destroyed vehicles were found near the bodies yesterday. Four other murder victims were found in other parts of the city in separate incidents, including a police chief, local media reported.

Drug violence has killed more than 30,000 people since President Felipe Calderon launched his army-led crackdown on drug cartels in December 2006.

Despite capturing and killing many top gang leaders since then, the government is still under enormous pressure to contain the violence and show that Mexico, an oil exporter and major emerging market economy, is still a safe place to invest in

After a brief Christmas lull, violence has again surged across the country, with at least 10 attacks on police and a prison in the city of Monterrey.