MEXICO CITY, July 13 (Reuters) - A drug gang has threatened to kill foreign journalists who report on the violence between rival cartels and security forces along the U.S.-Mexico border, media and U.S. officials said on Friday.

Mexico's cocaine smuggling Gulf Cartel has allegedly planned to hire gunmen to kill foreign journalists working in the crime-torn Mexican city of Nuevo Laredo, on the border with Texas.

In response, two Texas-based newspapers have pulled their reporters from the city.

The U.S. government condemned the threats and said it would try to protect U.S. journalists working in Mexico.

"We will work with authorities in the United States and in Mexico to do everything possible to guarantee the safety of U.S. journalists who work on each side of our common border," said Tony Garza, the U.S. ambassador in Mexico.

Mexico's foreign correspondents' association said it had information that any foreign journalists working in the area could be at risk.

Mexico's main drug cartels are locked in a violent struggle for control of regions key to trafficking South American cocaine and other drugs into the United States.

Mexican journalists are increasingly targets of threats and attacks, especially when they cover the drug gangs.

Press freedom group Reporters Without Borders says nine journalists were killed in Mexico in 2006 for reporting drug trafficking or violent unrest, making the country the second most dangerous country for reporters after Iraq.

The group called on Mexico's government on Friday to do more in response to attacks and threats against journalists from drug traffickers and some public officials.

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