A confidential memo from federal officials warns Border Patrol agents they could be the targets of assassins hired by the smugglers of illegal aliens.

According to the Associated Press, the alert, issued by the Department of Homeland Security, notes that illegal aliens have become increasingly annoyed by recent efforts to tighten the southern border of the United States.

The memo, dated Dec. 21, states smugglers plan to bring members of the Mara Salvatruchas gang – also known as MS-13 –into the U.S. to target the border agents.

Aliens from El Salvador began MS-13 in Los Angeles but also has a presence in Central America. The gang has been linked to al-Qaida and other terrorist organizations. Members have been known to behead victims and attack with grenades and machetes.

Federal officials estimate between 8,000 and 10,000 MS-13 members live in 31 states – the majority of them in the country illegally. Some 103 suspected members of the gang were rounded up during a seven-city operation in March.

AP reported FBI and Border Protection officials were not commenting on the confidential alert.

As WorldNetDaily reported, on New Year’s weekend, as many as 20 shots were fired from Mexico at agents near Brownsville, Texas, in the most recent of a series of incidents involving gunplay and other violence directed at Americans from south of the Rio Grande River.

The gunfire did not appear to be a random action and that the attacker – who was not identified in reports – was most likely a trained shooter, KRGV-TV, ABC’s Brownsville affiliate, said.

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