Mexico Drug War: More Than 20 Bodies Found

The bodies of 23 people have been found hanging from a bridge or dismembered in ice boxes and rubbish bags in Mexico.

The deaths are an escalation of violence involving rival drug gangs on the US border

In a first incident, the bodies of five men and four women were found hanging from a bridge in Nuevo Laredo, in Tamaulipas state, just across the border from the Texas city of Laredo.

Police could not confirm who was responsible for the murders but a message seen with the bodies indicated it may have been an attack by the Zetas cartel against the rival Gulf cartel.

Hours later, police found the dismembered corpses of 14 people in rubbish bags and ice boxes dumped near the police station of Nuevo Laredo, police investigators said.

They said the second massacre could have been an act of revenge for the earlier killings.

More than 50,000 people have died in drug-related violence in Mexico since President Felipe Calderon launched a crackdown on traffickers after taking office in late 2006.

He has deployed tens of thousands of federal police and soldiers across Mexico.

The Zeta cartel was founded by deserters from the Mexican special forces who became Gulf cartel enforcers and later split from their employers.

The two gangs are now fighting for control of local drug trafficking routes.

Last month, the dismembered remains of 14 men were found stuffed inside a minivan left near Nuevo Laredo's town hall.

Days later a car exploded outside police headquarters. Officers said the explosion was caused by a grenade.

Discontent over the bloody attacks is helping fuel support for the opposition Institutional Revolutionary Party, or PRI, ahead of Mexico's July 1 presidential election.

Opinion polls make the PRI the favourite to regain the presidency they held for most of the past century.

The Zetas have also been engaged in hostilities with the powerful Sinaloa cartel, named after the state in northwestern Mexico where violence has surged over the past week.

Sinaloa is the home turf of Mexico's most wanted drug trafficker, Joaquin "Shorty" Guzman, who heads the Sinaloa cartel.

Analysts say Guzman's killing or capture would boost Mr Calderon's embattled conservatives ahead of the presidential vote.