An elite reconnaissance team formed by former Texas Gov. Rick Perry in 2009 may have pushed the boundaries of international law, according to a published report.

According to internal Texas Department of Public Safety documents acquired by the Austin American-Statesman, Texas authorities performed aerial surveillance of drug cartel targets south of the Mexican border. In those documents, a key government contractor described the actions as “spying on Mexico.”

The documents reportedly say surveillance aircraft were used to track suspected Zeta cartel members and pass the information to Immigration and Customs Enforcement. “Using this information, ICE can work in conjunction with Mexican Military forces to target Los Zetas both north and south of the border to disrupt cartel trafficking operations.”

The newspaper claims the section was followed by a warming: “Need to be careful here as we are admitting to spying on Mexico.”

When contacted about the documents, the DPS told the Austin American-Statesman it did not have “information to speak directly” to the mission.

The documents did not specify how far into Mexico the surveillance occurred or whether Mexico granted permission for the surveillance. The documents also did not mention whether the surveillance efforts continued beyond 2010.

DPS officials said the agency “typically conducts border security operations in coordination with law enforcement partners at the local, state and federal level.”

U.S. surveillance of Mexico – with Mexican authorization – has increased as drug violence has run rampant over the past decade.

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