NEW YORK: An ISIS-inspired Bangladeshi-origin man, wearing a homemade device, triggered a blast at a metro station in New York City during the morning rush hours, injuring four persons and causing chaos in one of the busiest commuter hubs in the metropolis, officials said.

Akayed Ullah, the 27-year-old suspected bomber, had wires and a pipe bomb strapped to his body. The device prematurely exploded between two subway platforms near Port Authority, which is America's largest bus terminal, police said.

The suspect was taken into custody after the device partially exploded. The subway station was evacuated and Port Authority terminal was shut down.

Ullah was alone, the police said, adding that the explosion was recorded on surveillance video.

No group has claimed responsibility for the explosion so far, though it was being treated as terror-related.

"This was an attempted terrorist attack. Thank God he did not achieve his goal," Mayor Bill de Blasio told reporters.

"At this point in time, all we know of is one individual who, thank God, was unsuccessful in his aims," Blasio said.

"There are also no credible and specific threats against New York City at this time. But we will give you more information as the investigation unfolds," he said.

"Our lives revolve around the subway. The choice of New York is always for a reason, because we are beacons of the world. We show that a society of many background and many faiths can work...The terrorists want to undermine that. They yearn to attack New York City," he added.

A total of four injuries were reported at the scene of the explosion at Port Authority, the New York Police Department said, adding all injuries are non-life-threatening.

The suspect, who lived in Brooklyn, suffered serious burn injuries and is currently admitted at a hospital. He had arrived in the US some seven years ago from Bangladesh.

"Preliminary investigation at the scene indicates that this male was wearing an improvised low-tech explosive device attached to his body. He intentionally detonated that device," Police Commissioner James O'Neil told reporters.

President Donald Trump was briefed on the New York explosion, White House Press Secretary Sarah Sanders said.

The FBI has joined the investigation.

New York Governor Andrew Cuomo said that New Yorkers would not be disrupted by such an attempt.

"We are a target by many who would like to make a statement against freedom...Let's go back to work we are not going to allow them to disrupt us," he said.

"The reality is that we are a target by many who would like to make a statement against democracy, against freedom. We have statue of Liberty in our harbour and that make sus an international target. We understand that," he said.

Former New York Police Department Commissioner Bill Bratton told MSNBC that the man was inspired by the Islamic State terror group and originally came from Bangladesh.

Earlier, the New York Police Department tweeted that it was responding to reports of an explosion of unknown origin at 42nd Street and 8th Ave, Manhattan.

The New York Fire Department received call around 7.19 am.

"I was exiting the Port Authority and the National Guard was running towards something shouting 'Go, Go, Go'," commuter Keith Woodfin tweeted, according to New York Daily News.

Designer Chelsea LaSalle tweeted that she was "stuck in a running stampede at port authority bus terminal due to bomb scare. cops EVERYWHERE."

Security was enhanced in several major American cities after the explosion in the New York City.

"We are monitoring the incident that occurred in New York City this morning. At this time, there are no current threats to the District of Columbia. We ask all residents and visitors to remain vigilant," said the Washington DC Police Department.