Police arrested two North African-born men in a sting operation after they bought a hand grenade and guns to attack a New York City synagogue, authorities said on Thursday.

Algerian-born Ahmed Ferhani, 26, and Moroccan-born Mohammed Mamdouh, 20, bought three pistols, ammunition and an inert grenade after a seven-month sting operation, police and Manhattan prosecutors said in a statement.

The plot unraveled on Wednesday, becoming the 13th planned attack by Islamist militants on New York City since the Sept. 11, 2001, attacks.

New York has remained a target for al-Qaida and police have been on heightened alert following the May 2 raid in which U.S. special forces killed al-Qaida leader Osama bin Laden in Pakistan.

President & CEO of The Jewish Federations of North America Jerry Silverman issued a statement Thursday in response to the foiled terror plot, saying he was "disturbed by the news reports of a homegrown terror plot aimed at Jewish communal institutions in New York City."
Silverman commended the New York police department and intelligence agencies for neutralizing the threat, adding that in the wake of Osama bin Laden's killing, North American Jewish communities must be on the alert for heightened threats.
In a separate case two years ago, four men were arrested for placing what they thought were explosives outside synagogues in New York City's Bronx borough.

The men, who were caught in an FBI sting operation, were videotaped making vitriolic anti-Semitic statements to an FBI informant. They were convicted following a trial in Manhattan federal court and await sentencing.