"If you want to be safe, I would argue New York is the place that you want to go," he told reporters.
CBS News correspondent Jim Stewart reports that every time a bomb goes off in the world, a highly specialized NYPD unit searches local businesses for ingredients that make up the explosives – even a
"It's super, super strong volume, and this is what you need in order to make the bombs that were made in England," detective Jason Goldberg told Stewart.
Police said the city had increased the number of critical response patrol vehicles, and heavily armed teams swept through several hotels. Special attention was paid to hotels in midtown and downtown Manhattan, police said, declining to provide further details. One patrolling officer said units were instructed to watch for suspicious packages and activity.
Police officers and squad cards were posted early Thursday at midtown hotels including the Grand Hyatt New York, next to Grand Central Terminal.
Most visitors seemed unruffled and went about their business as usual Thursday, saying they trusted the city's terrorism expertise.
"You have to have faith," said Washington state Senator Linda Parlette, who was attending a conference at the Grand Hyatt. "New York has been through a tragedy with 9/11, and if anywhere there is going to be good security, it will be in New York City."
"We are not going to let it take us over," declared Cindy Yasumatsu, of Calgary, Canada, who was in town to celebrate her mother's 65th birthday. "We are going to have a good time."
But Randall Rose, a longtime doorman at the hotel, which has more than 1,300 rooms, said he noticed unease among a few guests.
"You can see it in their eyes," he said. "They don't say anything but they're looking around."
In Washington, the Homeland Security Department was not yet asking state and local officials to ramp up security in the wake of the Jordan bombings, a spokesman said. That could change if information indicated a credible domestic threat linked to the attacks, the spokesman said.
The department supports local decisions to raise security measures, the spokesman said.
In Jordan, the suicide bombers detonated explosives at the Grand Hyatt, Radisson SAS and Days Inn hotels in the capital of Amman. One of the explosions went off inside a hall where 300 guests were celebrating a wedding.
Al Qaeda claimed responsibility Thursday for the attacks. The claim appeared on an Islamic Web site that serves as a clearinghouse for statements by militant groups.