An exchange of personnel between the New York Police Department and the Jordanian National Police has allowed the police commissioner, Raymond Kelly, to keep tabs on security issues in Jordan, including potential threats to America. While police said no specific threat was actually made to New York hotels in the wake of Wednesday’s suicide bombings at three Western hotels in Amman, Jordan, the Police Department increased security at city hotels.

As soon as an hour after the three nearly simultaneous explosions in the Jordanian capital, the New York Police Department deployed 70 to 100 squad cars to two-dozen hotels in Midtown and downtown Manhattan, a Police Department spokesman, Inspector Michael Coan, said. Yesterday morning and afternoon, officers were sent to patrol other hotels.

“We have not gotten any threats to our hotel system, but it’s a normal precaution that you would expect us to take, and we did it,” Mayor Bloomberg said yesterday morning. He stressed that he thought “the message has to be: Continue your life and leave security to the professionals.”

The Police Department is working with the Metropolitan Transportation Authority and the FBI to keep the city’s hotels safe, Mr. Coan said.

The MTA increased its police presence in and around Grand Central Terminal and Penn Station with additional canine and “Samson” teams, which carry heavy weapons, a spokesman for the transportation authority, Thomas Kelly, said. Police were also said to have been deployed to open track beds and major stations on the Long Island Rail Road and Metro-North. “We’re on a heightened state of alert, with high visibility,” Mr. Kelly said. The transportation police stepped up reconnaissance, he noted, and was on course to conduct bag searches as needed. Concrete bollards and barriers were erected to harden Grand Central against potential truck bombs.

The NYPD was able to act quickly after receiving information from a sergeant assigned to a post in Jordan. He is looking at methodology, type of bombs used, and where they were put together, Mr. Coan said. The sergeant gleaned some of his knowledge from sitting in on a briefing with King Abdullah II of Jordan yesterday, Mr. Coan said.

The sergeant was in Jordan at the time of the explosions because an overseas assignment that had already been scheduled placed him in Amman on November 1, the same day a colonel from Jordan was sent to work in the counterterrorism intelligence division in Manhattan.

The Jordan assignment was the NYPD’s latest placement overseas, expanding the number of operatives sent abroad to gather terrorist-related information to nine. In January, an officer is expected to be sent to Australia.

New York’s attention to hotel security came in response to the deadly bombings in Jordan at the Radisson SAS Hotel Amman, the Grand Hyatt, and the Days Inn. There were more than 50 deaths and in excess of 100 injuries.

“The exact number of casualties from the blast has still not been determined,” Raddison said in a statement. “All casualties were among those attending a wedding reception where the blast occurred. One hotel employee, a banquet server, has been confirmed as a fatality of this incident.”

Three of the four guests injured by the blast in front of the Days Inn died yesterday, a spokesman for Days Inns Worldwide, Richard Roberts, said.

Following the attack, the Grand Hyatt made the following statement: “We cannot confirm the number of injuries at this time in what appears to be a tragic situation.”

It is important that hotels protect themselves because terrorists are likely to strike a New York City hotel, or maybe even a restaurant or the transportation system, said the chairman of the Cavalry Security Group, a company specializing in security assessment. “If my hotel has high security and yours has none, you’re dog meat,” Patrick Garvey said. Furthermore, the terrorists will “seek the soft spots where you get the biggest bang for your suicide bomber,” he said.

One hotel security expert, Mark Slovensky, said that while his employees can check bags and room keys, some visitors are bound to slip through. “It’s almost impossible to ID everybody” going in and out of hotels, Mr. Slovensky, president of the consulting security firm Gold Shield Group, said. “It’s a very hard thing” to manage, he said.

New York City’s tourism industry did not seem to be affected by the increased police presence as of early last evening, though it was only one day after the Police Department stepped up its hotel patrols. Cristyne Nicholas, the president and chief executive officer of NYC & Company, the city’s official tourism marketing organization, said her office had not received any calls about hotel reservation cancellations since news broke of the enforcement effort. She said she does not anticipate that the increase in police personnel will serve as a deterrent to tourists because New York’s officers have become “tourism icons.”