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Car bomb explodes outside newspaper offices in northern Mexico

Daniel Becerrill / Reuters

Resident look on after six men were shot dead in Monterrey, Nuevo Leon, on Monday. While four of the dead were suspected drug gang members, a fifth worked at a nearby car dealership and a sixth was offering to clean the windows of passing cars, according to local media. The graffiti on the wall reads "Cartels united."

A car bomb exploded outside the offices of a newspaper in the capital of Mexico's northern state of Tamaulipas on Monday night, according to the state government, the latest in a spate of violent incidents to rock the country.

Earlier on Monday, six men were shot dead in Monterrey, in the neighboring state of Nuevo Leon. Four were suspected drug gang members and two innocent bystanders, Reuters reported, quoting local media.

On Sunday, 12 police were killed in a mountain highway ambush hours after the severed heads of 10 people were dumped in a small town in a key illegal-drug-growing region in the southern state of Guerrero. Armed assailants opened fire on a police convoy, killing the dozen officers and wounding 11 more, said Arturo Martinez, spokesman for the state government, according to Reuters.

The ambush took place on a rural highway near the town of Teloloapan, located between the beach resort of Acapulco and Mexico City. Earlier Sunday, the severed heads of 10 people were lined along a street outside a slaughterhouse in the center of Teloloapan.

The La Familia cartel and its offshoot, Los Caballeros Templarios (The Knights Templar), are among the gangs fighting for territory in the region. The heads had been left with a message threatening the La Familia gang, local media reported.

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More than 50,000 people, including more than 2,500 police and soldiers, have died in drug-related violence since President Felipe Calderon launched an army-led crackdown on the cartels after taking office five years ago.

Car bomb
The car bomb in Ciudad Victoria, Tamaulipas, exploded at around 8:15 p.m. (9:15 p.m. ET) outside the offices of Expreso newspaper, according to a statement by state government (Link to statement in Spanish). Nobody was hurt in the explosion, which hit during the busiest time of day in the newsroom, but it did damage at least five cars and caused a fire, according to Blog del Narco, a site that documents the rising drug violence. (Link to website in Spanish)

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According to Blog del Narco the newspaper posted a notice on its site shortly after the bombing but msnbc.com was unable to access the posting.

It would not be the first time that journalists were apparently targeted in Mexico, one of the most dangerous countries in which to be a reporter or photographer. Many news organizations are wary of reporting on drug-related violence as a consequence.

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Blog del Narco has become one of the few sources of information about the ongoing violence. Comments on posts indicated that it is followed by those involved in the drug trade.

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Msnbc.com staff and Reuters contributed to this report.