U.S. federal prosecutors announced Tuesday that they have decided to drop a high-profile anti-corruption case that involved an undercover sting operation to catch bribery of foreign officials.

Federal prosecutors said in a court motion that they would discontinue the indictments against 16 defendants who, along with six others, were accused of violating the Foreign Corrupt Practices Act by trying to bribe foreign officials to secure business contracts.

"The government respectfully submits that continued prosecution of this case is not warranted under the circumstances," prosecutors said in the motion, citing setbacks in previous trials of the case.

A total of 22 executives of the military equipment industry were arrested and indicted over two years ago in a sting operation the U.S. Justice Department boasted as an example of its efforts to enforce the 1977 law against foreign bribery.

During the operation, FBI agents posed as representatives of Gabon's defense ministry to lure the executives to reach a 15- million-dollar deal of military equipment procurement in which the executives agreed to offer 1.5 million dollars as commission to the defense minister.

In previous trials, three defendants were acquitted and another three pleaded guilty. The remaining 16 were waiting for trial or re-trial.