WASHINGTON – The U.S. government is demanding an in-depth investigation of what one congressman terms “another Mexican military incursion” and what the Border Patrol agent on the scene called “an act of war.”

Rep. Tom Tancredo, R-Colorado, has led a one-man crusade over the incident in Arizona in which at least one shot was fired at a Border Patrol agent. Now, the Immigration and Naturalization Service issued a statement indicating the U.S. government is asking Mexico City to explain what happened.

The attack took place Friday night, according to Tancredo’s Border Patrol source, along the U.S.-Mexico border near Ajo, Ariz. According to the unnamed agent, the Tohono O’odham Police Department encountered the Mexican army unit about 8:30 p.m. along the Santa Cruz trail inside the Papago Farms border patrol area, just south of Forest Road 21. The area is between five and 10 miles inside Arizona.

“I cannot in good conscience stand by and watch another incursion along our border take place,” Tancredo said.

“Unless we open our eyes and recognize that what’s happening along the U.S.-Mexico border is real, one of our guys is going to get killed. Everyone keeps claiming that these ‘incursions’ don’t take place, that people are just getting lost, and the whole idea of incursions is erroneous. Unless the U.S. and Mexican government admits these incursions exist and take action to stop them, then an international incident, in my opinion, is foreseeable,” concluded Tancredo.

This is the latest of a series of similar incidents along the U.S.-Mexican border – from California to Texas. Tancredo cites 23 such incursions last year alone. Several have occurred in recent weeks.

The U.S. Border Patrol agent, who wishes to remain anonymous, told Tancredo during a phone conversation that one of his colleagues noticed a military helicopter flying overhead about five miles north of the U.S.-Mexico border. The chopper was heading south toward Mexico.

Shortly after, he came upon a Humvee, which not only began to approach him, but to fire upon his vehicle. According to the agent’s testimony, the vehicle’s rear window and back driver’s-side windows were destroyed. Fortunately, the agent was able to flee the incursion unharmed. He concluded the conversation with Tancredo saying, “As far as I am concerned, that [incursion] should be an act of war.”

Even before this latest incident, Tancredo issued a letter to Mexican President Vicente Fox demanding he reveal the details of these “incursions” made by members of the Mexican army and law enforcement agencies on American soil. Tancredo never received a response to the May 3 letter.

Friday’s incident may not have been an official incursion, but rather a case of criminals using military uniforms, Rodriguez Hernandez, the former Mexican consul in Nogales told the Arizona Daily Star. Lawbreakers have used military and police uniforms in recent years along this stretch of border, he said.

Tancredo believes the Mexican soldiers are providing cover to drug smugglers along the border. Friday’s incident occurred near a smuggling hot spot. Mexican soldiers have been caught many times corruptly helping drug smugglers. But they have also served as Mexico’s top troops in the drug war, scoring important gains such as the arrest in March of the most-wanted kingpin, Benjamin Arrellano Felix.

The Mexican government said it believes the attack came from drug traffickers dressed up as Mexican soldiers.

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