Not all New Yorkers are reassured that the city is in the clear after authorities foiled a plot to blow up a jet fuel pipeline that runs under densely populated New York City neighborhoods.

A day after authorities accused four men of plotting to attack the pipeline, which services John F. Kennedy International Airport in Queens, New York residents and politicians questioned the city’s vulnerability as another potential target was added to the city’s running list.

“The pipeline is a ticking time bomb because anyone can go down there at any time,” a retired city worker who lives a block from the pipeline in Brooklyn, Morton Pupko, said.

The pipeline’s operator, Buckeye Partners, has said that in the event of an attack, sections of the 40 miles of pipeline that run between Linden, N.J., and Queens could be isolated easily by shutoff valves.

The president of Accufacts Inc., a company that investigates oil and gas pipelines, Richard Kuprewicz, said an explosion in the pipeline would probably extend for hundreds or thousands of feet, not miles.

“There have been neighborhoods that have disappeared — a tremendous fireball and tremendous amount of destruction,” he said. “It’s going to be fairly spectacular, but it’s going to be limited.”

Mr. Kuprewicz gave the recent example of a pipeline that exploded in an uninhabited park in Bellingham, Wash., killing two 10-year-old boys and a teenager. In that case, operators were charged with mishandling a leak.

Mr. Kuprewicz said he believed that in New York the pipeline was monitored more carefully.

Authorities said Saturday that the pipeline plot had been hatched last year by a former JFK cargo worker, Russell Defreitas, 63, who is a naturalized American citizen from Guyana. Law enforcement agencies, including the NYPD and the FBI, monitored Mr. Defreitas for a year as he sought to follow through with the scheme, including allegedly seeking help from a former member of the Guyanese parliament, who also was detained.

New York politicians said yesterday that the plot supported their arguments that the city deserves more federal counterterrorism funding from the Department of Homeland Security. The department is due to announce how much the city will receive at the end of the month.

“It certainly demonstrates that New York needs more money, and that New York is the no. 1 target,” Rep. Peter King, a Republican of Long Island and the ranking member of the Homeland Security Committee, said.

The city is expected to receive a larger percentage of the funding this year than in previous years after New York politicians, including Mayor Bloomberg, protested the way the money is handed out. But Mr. King said the new amount would not be enough to combat the various threats they city faces.

Rep. Vito Fossella, a Republican of Staten Island and Brooklyn, said coordination, not necessarily money, was needed to prevent an attack.

“There’s got to be a meeting of minds from one end of the pipeline to the other,” he said.

An NYPD spokesman, Deputy Commissioner Paul Browne, said New York police had stepped up security around the pipeline since learning of the plot, including regular patrols by aviation and harbor units.

City Council Member Peter Vallone of Queens warned that news of the plot added urgency to another problem the city could face this summer: a police recruitment crisis. Today he is presiding over a City Council hearing to address a shortfall in recruits, which both the department and police unions have blamed on a low starting salary.

“I can’t think of another police department that has been downsizing since September 11,” he said. “This plot shows us that we need more boots on the ground watching sensitive locations, not less.”