US Ambassador Tony Garza condemned threats against US reporters amid intelligence reports that drug traffickers were planning to kill foreign journalists along the US-Mexico border.
In a statement on Friday, Garza condemned threats against journalists as "an attempt to intimidate them from reporting the truth."
A US Embassy official said on condition of anonymity that US law enforcement officials have reliable information that drug traffickers are planning to target foreign journalists.
While past attacks have targeted local reporters, the threat against foreign journalists indicated that drug traffickers are becoming bolder in their attempts to silence news reports on their activities.
"We will work with authorities in the US and Mexico to do everything possible to ensure the safety of American reporters working along both sides of our common border," Garza said.
The embassy official said the threats appeared concentrated around the violent city of Nuevo Laredo, where a new police chief was gunned down two years ago hours after taking office, and hundreds of people have been killed in drug violence since.
Erik Vasys, spokesman for the FBI in San Antonio, Texas, said that "at this time, we are not aware of a specific threat to harm or injure any specific person or media entity."
"The FBI will use all of its resources to protect the free press from violence and intimidation," Vasys said.
The San Antonio Express-News pulled its correspondent, Mariano Castillo, out of Laredo, Texas, across the border from Nuevo Laredo, late on Thursday in light of the threats.
In a story posted on the newspaper's Web site on Friday, editor Robert Rivard said the paper was told by an official that a drug cartel was seeking to put out a hit on an American reporter in Laredo.
"We don't know that the report is credible and we hope it isn't," he said. "But until we feel comfortable knowing that, we're going to err on the side of caution."
Eloy Aguilar, president of the Foreign Correspondents Association in Mexico, sent out an e-mail advising foreign correspondents to "be extremely careful and security conscious."
Aguilar, who retired last year as Associated Press bureau chief in Mexico City, said the warning was "based on journalists who have been there and were told by sources on both sides of the border that there was a threat that was considered serious enough to be taken into account."
A television crew for the TV Azteca network disappeared in Monterrey in May, and an Acapulco correspondent was gunned down in April.