In a call to New York City's terrorism hot line in May, the informant described the plot in chilling detail: Syrians working in the jewelry business had hatched a plan to carry out a suicide bombing in the subway system on one of the most symbolic days of the year, Independence Day.
They had hidden explosives in hollowed-out jewelry, the informant said, and then used their professional know-how to import the jewelry and bring it to a store that one of them owned in New York.
To clinch the story, the informant, who identified himself as Jose Rodriguez and said he was from Israel, told the police officer answering the hot line that he had overheard the plotters use the Arab expression ''Allahu Akbar,'' or ''God is great.''
The post-Sept. 11 antiterrorist law enforcement apparatus sprang into action, with city, federal and even Israeli officers following leads, conducting 24-hour surveillance and searching homes and businesses with bomb-sniffing dogs. A New York detective stationed in Jerusalem tried to track down the man called Jose Rodriguez.
In the end, the investigators concluded that the call was a hoax, they said yesterday, perpetrated by a Syrian Jewish refugee named Rimon Alkatri, 34, the owner of a jewelry store in Brooklyn. The five conspirators identified by Mr. Alkatri were not Muslims but Christians and Jews, the police and prosecutors said. He had done business with four of the men, officials said, and had named them as terrorists because he had a grudge against them stemming from a business deal that had ended in a bitter disagreement.