Mexican President Felipe Calderon's administration said Wednesday it is sending troops and federal police to a Gulf coast state where gunmen dumped 35 bound, seminude, tortured bodies on a busy avenue in front of horrified motorists.
Federal security spokesman Alejandra Sota said the federal forces will reinforce operational and intelligence work in the state of Veracruz. She didn't say how many troops and officers are being sent.
Sota said Veracruz's government asked federal prosecutors to take over the investigation of last week's body dumping.
Authorities have said the victims were linked to the Zetas drug cartel. The killers are believed to be from the New Generation gang, a group that is associated with the Sinaloa cartel.
The area had been dominated by the hyper-violent Zetas cartel, while Sinaloa is challenging their control.
Banners appeared in some Veracruz cities over the weekend accusing Mexican marines, who have taken a leading role in the government's offensive against cartels, of kidnapping residents and favoring the Sinaloa cartel.
On Wednesday, the navy said marines had detained three people who were carrying similar banners in their vehicle near the Gulf coast port of Tuxpan in Veracruz state. The three are believed to be linked to the Zetas, the navy said.
Marines pulled over their sport utility vehicle at a highway checkpoint Tuesday and found the banners, ammunition and a small amount of cocaine inside, the statement said.
The Zetas have extended their operations inland from the Gulf coast, and state police in the neighboring state of Hidalgo reported that two officers were wounded by grenade fragments in a shootout with alleged Zetas. One of the attackers was killed in the confrontation.
The assailants abandoned a vehicle with a grenade, two assault rifles and about 1,000 rounds of ammunition inside, authorities said.
In Tamaulipas state, to the north of Veracruz state, officials in the state attorney general's office said the hacked-up and burned body of a man believed to be a federal police officer was left on a road in the state capital. State and federal police could not confirm the man's identity.
A message left with the body said the Zetas had carried out the killing, in retaliation for the officer's alleged support for the Zetas' main rival, the Gulf cartel, said the officials, who spoke on condition of anonymity.
Federal police have been sent to several hotspots throughout Mexico to supplement often corrupt, intimidated or weakened local police.
In Ciudad Juarez, a border city where thousands of federal officers have been posted, the federal Attorney General's Office announced that 10 former federal officers had been arrested and ordered to stand trial on charges of extortion, abuse of authority and drug possession, among others.
Prosecutors said the officers were detained earlier this month on a citizen complaint. They were caught with a captive man in their vehicle, who told investigators the police had threatened to plant drugs on him and demanded money in return for releasing him.
An inspection of the officers' patrol vehicles found heroin, marijuana and unlicensed guns, prosecutors said.