NEW YORK, Sept 22 (Reuters) - Manhattan federal prosecutors' efforts to capture suspects outside the United States and bring them to New York to face charges were substantially upheld by a U.S. appeals panel.

In an opinion on Wednesday, the 2nd U.S. Circuit Court of Appeals in New York affirmed the increasingly prevalent government tactic of using sting operations to trap arms and drug traffickers worldwide.

The opinion could have implications for a small handful of cases currently in Manhattan federal court, where defense attorneys have argued the U.S. has vastly over-extended its jurisdiction in capturing suspects.

The case discussed in the opinion was of Monzer Al-Kassar and two co-defendants.

Kassar, a Syrian native and longtime resident of Spain known as the "Prince of Marbella," was arrested after he agreed to sell weapons to U.S. Drug Enforcement Administration (DEA) informants posing as members of the FARC, the militant Colombian group. The informants told Kassar they intended to use the weapons against U.S. forces in Colombia.

Kassar's attorneys argued on appeal that U.S. prosecutors were not allowed to charge non-U.S. citizens caught in a sting operation abroad. The appeals court conceded that Kassar "never came close to harming any U.S. person or property," but concluded that was "irrelevant for conspiracy offenses, which often result in no palpable harm." Instead, the court said the government had clearly established Kassar's intent to harm the U.S.

The circuit also found the government had not "manufactured" jurisdiction by creating the chance for Kassar to break the law.

"While it is true the DEA agents lied to the defendants, this does not make the nexus (to the U.S.) artificial or invalid."

Questions about the extent of the U.S government's reach have been raised by defendants in a handful of cases in Manhattan federal court, including suspected Russian arms dealer Viktor Bout, an Eritrean man suspected of aiding Somali militants, Mohamed Ibrahim Ahmed, and Swedish arms-dealing suspect Paul Mardirossian.

Kassar was sentenced by U.S. District Judge Jed Rakoff to 30-years in prison in 2009. His co-defendants both were handed a 25-year sentence.

Kassar's case was heard in February by circuit judges Dennis Jacobs and Peter Hall, and district judge Shira Scheindlin.

The case is USA v. Monzer Al Kassar et al., 2nd U.S. Circuit Court of Appeals, No. 09-1051.

(Reporting by Basil Katz)

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