NEW YORK -- Three men in a stolen car were arrested by federal agents on a stakeout near a mosque in Brooklyn, and chemicals used in bombs were found in a locker in New Jersey yesterday as authorities intensified the investigation of the man they described as an Islamic fundamentalist who is charged in the car bombing of the World Trade Center.
There were no indications that the men seized in Brooklyn had taken part in the bombing a week ago, and in fact authorities sought to play down the importance of the action. But the arrests and the discovery of bomb materials in a warehouse in Jersey City signaled a widening hunt for clues and suspects in the case.
The authorities were particularly interested in anyone with ties to Mohammed A. Salameh, an illegal alien living in Jersey City, who was arrested at a truck rental agency there Thursday and charged with taking part in the bombing that killed five people, injured 1,000 others and crippled the trade center.
At a warehouse in Jersey City yesterday, investigators found hundreds of pounds of industrial chemicals that they said could be used to make a bomb.
Two of the chemicals -- nitric acid and sulfuric acid -- are ingredients in nitroglycerin.
While the bomb materials used at the trade center have not been identified, traces of nitrates were found, and bomb experts said the chemicals found yesterday could have left such traces.
Much about the case remained murky yesterday: the motives, identity and number of the conspirators, the kind of explosives used and the role of Mr. Salameh, who was arrested after investigators found an identifiable fragment of a van in the rubble and traced it to the Jersey City truck rental agency where it had been leased by Mr. Salameh three days before the blast.
As new details of Mr. Salameh and his associations and background emerged, officials said the 25-year-old suspect rented the van that carried the bomb but was apparently not a ringleader of the conspiracy.
Authorities describe Mr. Salameh as a follower of an Egyptian cleric linked by Egyptian authorities to a radical Islamic group that has committed assassinations and terrorism.
Federal officials said Mr. Salameh, who is being held without bail, had come to the United States from Jordan in 1988 and had lived here illegally for more than four years after entering on a six-month tourist visa that expired.
There were no indications that he had left the country since then, but it was unclear what he had done here or exactly where he had lived overthe past four years.
Though he carried a Jordanian passport, Mr. Salameh's nationality could not be determined. Many Palestinians use Jordanian passports.
In recent months, however, he had lived in Jersey City and attended a mosque that was the base of Sheik Omar Abdel-Rahman, who has been linked to the 1981 assassination of President Anwar Sadat of Egypt. Sheik Rahman is widely regarded in Egypt as a spiritual leader of radical groups that make up the Egyptian branch of Islamic Jihad, or Holy War, a group identified with many acts of terrorism.
Meantime, another associate of Mr. Salameh who was also arrested Thursday, Ibraham A. Elgabrowny, was ordered held without bail yesterday in a U.S. court hearing in Manhattan.
Mr. Elgabrowny is a cousin of Sayyid A. Nosair, the man who was tried for the 1990 assassination of Rabbi Meir Kahane.
At the hearing, prosecutors disclosed that a number of false passports for the jailed Nosair and other members of his family had been found in Mr. Elgabrowny's Brooklyn apartment after his arrest.
One law-enforcement official said authorities were investigating the possibility of yet another conspiracy -- to arrange the escape of Nosair from an upstate prison so that he and his family might flee the country.
A prosecutor at the hearing, asked by Judge Richard Owen to justify his request for no bail on a relatively minor charge of obstructing justice -- throwing a punch at a federal agent who searched his home Thursday -- said Mr. Elgabrowny might well be tied to the trade center bombing.
"We are investigating whether there is a link of this defendant to the bombing at the World Trade Center," the prosecutor, Henry DePippo, declared. "The government would argue that he is a serious risk to obstruct justice in this case."
Mr. DePippo, describing the defendant as a bail risk who would flee if given the opportunity, said investigators were still examining a gun, ammunition and other materials confiscated at Mr. Elgabrowny's apartment, which was searched on a warrant issued in connection with the trade center bombing.
Mr. DePippo also disclosed that the suspect, after his arrest, had been told not to wash his hands or put them in water, suggesting that they were to be examined for traces of bomb-making chemicals.
Soon afterward, Mr. DePippo said, Mr. Elgabrowny asked to go to the bathroom and, when given permission, plunged his hands into a toilet bowl containing urine.
Mr. Elgabrowny's lawyer, Michael Warren, who had been one of Nosair's lawyers, explained the toilet bowl incident by saying that as a Muslim, the defendant was obligated to cleanse himself before praying.
Mr. Warren also challenged the validity of the search warrant and asked that his client be released on bail, saying he had "roots in the community," was married to an American and had a business.
"There is absolutely nothing in these papers that would link Mr. Elgabrowny to the bombing at the World Trade Center," Warren said.
But Judge Owen rejected these arguments, saying Mr. Elgabrowny had been linked to "the man charged with renting the van that practically blew off the southern end of Manhattan island," and he added, "This is not a case of just striking agents. This is a case of a man being aware that something is going on that he may be in up to his eyeballs."
In another development, Gov. Mario M. Cuomo asked PresidentClinton to issue a major disaster declaration in connection with the trade center explosion so that New York state can obtain federal aid for those thrown out of work because of the blast and for repairs to the trade center and improvements in its security system.
In a letter to the president, Mr. Cuomo estimated that the explosion on Feb. 26 had caused at least $705 million in business losses, structural damage and security costs.
"This event appears to be of such severity and magnitude that effective response is beyond the capabilities of the state and New York City," the governor wrote.
The Small Business Administration has already agreed to provide low-interest loans to businesses hurt by the disaster.