Mexican authorities say at least 14 bodies have been found in the Pacific beach resort city Acapulco.
Officials say several of the bound and blindfolded victims had drug gang messages left near their bodies Friday.
Elsewhere in Mexico, two car bombs exploded in the northern Mexican state of Tamaulipas, where officials are investigating the massacre of 72 migrants.
An explosion outside the studios of the Televisa station temporarily knocked out its signal Friday, but no injuries were reported. Authorities say the second blast happened in front of the offices of the traffic police.
The blasts happened three days after the remains of the migrants, believed to be from Central and South America, were discovered on a farm in the state.
Authorities say Roberto Jaime Suarez, the prosecutor investigating the massacre of the migrants in Tamaulipas, has been missing since Wednesday.
Tamaulipas borders the southwestern U.S. state of Texas, and has been the scene of deadly violence among drug cartels fighting for control of the area.
In a related development, the U.S. State Department is telling diplomats in the northern Mexican city of Monterrey to remove their children from the area. Authorities cited an August 20 shooting in front of an American school in Monterrey and the growing threats of kidnapping. Officials say that beginning September 10, the Consulate General in Monterrey will become a partially unaccompanied post with no minor dependents of U.S. government employees.
The Monterrey area increasingly has been plagued by violence arising from clashes among rival drug gangs. Monterrey is the capital of the state of Nuevo Leon, which also has seen an increase in drug-related violence.
More than 28,000 people have been killed in Mexico's drug war since President Felipe Calderon took office in late 2006 and began cracking down on the cartels.
Some information for this report was provided by AP and Reuters.