NEW YORK -- Four people suffered minor injuries and a man is in custody after an explosion in the subway under the Port Authority Bus Terminal in Manhattan that Mayor Bill de Blasio called "an attempted terrorist attack."
A pipe bomb affixed to the suspect with Velcro straps detonated at about 7:20 a.m. Monday in the passageway between subway lines that runs a full city block under 42nd Street between 7th and 8th avenues.
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The suspect, identified as 27-year-old Akayed Ullah, suffered burns to his arms and torso from the device that went off. He is alert and conscious but badly injured at Bellevue Hospital, sources say.
"Preliminary investigation at the scene indicates that this male was wearing an improvised low-tech explosive device attached to his body," NYPD Commissioner James O'Neill said. "He intentionally detonated that device."
Governor Andrew Cuomo said that while Ullah intentionally detonated the device, the pipe did not fully shatter so it did not have the desired effect. The governor also said Ullah signaled to police he learned to make the device from online instructions and his motive was he was "angry."
During a series of interviews Monday afternoon. Gov. Cuomo also proposed that internet providers should consider their responsibility when they know a user is downloading information on how to hurt people. "It's a question we will have to deal with," he said.
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Ullah, whose address is in Brooklyn, is from Bangladesh and has been in the United States for seven years. He came to the U.S. on an F-4 visa, a preferential visa available for those with family in the U.S. who are citizens or permanent residents, and officials believe he made the bomb in his apartment in an attack he planned for about a year. Authorities said he was speaking with investigators from his hospital bed, and that he made statements indicating he supports ISIS.
He has a brother in a Brooklyn school that authorities are now trying to find, and investigators were also searching his apartment and interviewing relatives.
The suspect currently works as an electrician but has worked as a taxi driver in the past.
Four civilians suffered minor injuries.
PHOTOS: Pipe bomb explosion at Port Authority Bus Terminal in New York City
"This was an attempted terrorist attack," de Blasio said at a news conference. "Thank God the perpetrator did not achieve his ultimate goals."
Cuomo asked New Yorkers to be alert but go about their lives.
"Let's go back to work," he said. "We're not going to allow them to disrupt us."
The bus terminal was temporarily closed but later re-opened, and subway service was disrupted throughout the morning but has since returned to normal with delays.
There was a massive police response in the area surrounding the terminal, but authorities stressed there were no additional credible threats against the city. Still, the NYPD was beefing up security at high-profile sites across the area.
Authorities confirm the bomb squad searched for a second possible device, which is normal procedure after an explosion.
Streets were closed off in the vicinity of the bus terminal, snarling traffic during rush hour. Most streets have reopened.
Bus riders were advised to expect delays and service changes in Midtown.
The NYPD, FDNY and first responders were all at the scene.
The White House praised the first responders at an afternoon news conference: "On behalf of the President and a grateful nation, we would like to thank them and commend them for their bravery."
Mayor: New York City explosion was attempted terrorist attack
NYC PORT AUTHORITY SUBWAY EXPLOSION