Mexican authorities on Friday announced the arrest of 20 drug-cartel gunmen, including eight suspects linked to 67 killings in the Gulf coast state of Veracruz.

The arrest of the the eight murder suspects occurred Thursday in the Boca del Rio-Veracruz city metropolitan area "as a result of intelligence work," the spokesman for the navy department, Jose Luis Vergara, said at a press conference in the Mexican capital where the purported cartel enforcers were paraded before the media.

The group of eight told investigators they were members of the Jalisco Nueva Generacion cartel, which also goes by the handle "Los Mata Zetas" (The Zetas Killers), he said, identifying Alfredo Carmona as the leader of the cell.

Several video clips with footage of a group of armed and hooded individuals were distributed after 35 bodies were dumped last month under a busy overpass in the Veracruz metro area.

Authorities said the killings were a settling of scores among drug gangs and that the vast majority of the victims had criminal records.

On one video, a spokesman said he and his comrades were waging an extermination campaign against the Los Zetas cartel and described the group as vigilantes who do not extort or kidnap and only aim to drive their rivals out of Veracruz state.

Following the appearance of the clips, some analysts said the group might be an independent death squad that enjoys some support from the authorities or from business leaders tired of being extorted by organized crime elements.

But Vergara said Friday Jalisco Nueva Generacion was "just another organized crime gang" and that it was battling the Zetas for "control of illegal activities and resources" in Veracruz.

The Mata Zetas are a splinter group that emerged following the 2010 death of Ignacio "Nacho" Coronel, who was one of the kingpins of the powerful Sinaloa cartel, he said.

The eight suspects led authorities to three safe houses where 32 bodies were found later Thursday.

Vergara said there is evidence that the eight suspected Jalisco Nueva Generacion members also are linked to the other bodies found under a busy Boca del Rio overpass on Sept. 20.

Taking into account all the corpses discovered in recent weeks in the Veracruz metro area, a total of "67 people have presumably been killed by this criminal gang," the spokesman said.

During the operation, marines seized three vehicles, five rifles and six handguns, 1,707 rounds of ammunition, communications gear and computer equipment, among other items.

Separately, another operation carried out Thursday in Veracruz led to the arrest of 12 members of Los Zetas, including Aquiles Amaranto Cruz Hurtado, reputed to be the cartel's local chief.

The arrests came just a day after federal forces were deployed to the Gulf coast state as part of "Operation Safe Veracruz," which also involves cleaning up local police departments and strengthening intelligence efforts to bolster security across the state, which has been battered by a wave of drug-related violence.

The federal government said Wednesday it is responding to the violence in Veracruz by improving coordination with local authorities "to protect the lives of all Mexicans and guarantee the security of families in every community."

Mexico's interior minister, Jose Francisco Blake, said of the operation that federal forces will be deployed across Veracruz state under a unified command to "regain (control of) the areas invaded by crime" and gather intelligence to dismantle the logistical, operational and financial networks of criminal organizations.

The Los Zetas and Gulf cartels, as well as some breakaway members of the once-powerful La Familia Michoacana mob, are the most active criminal elements in Veracruz state, authorities say.

The Zetas are a gang of Mexican special forces deserters turned outlaws who are notorious for brutally murdering their rivals and for a massacre of dozens of undocumented immigrants who apparently refused to work for the gang as enforcers or couriers.

Drug-related violence in Mexico has left more than 40,000 dead since President Felipe Calderon militarized the struggle against the heavily armed, well-funded cartels shortly after taking office in December 2006.