New York, United States: New York authorities said Monday they are seeking a 28-year-old man in connection with a bombing in the city that injured 29 people.

Police and the FBI released a photo of Ahmad Khan Rahami, a naturalized US citizen of Afghan origin, saying he was "wanted" for questioning in the explosion Saturday night in the Chelsea neighborhood. 

New York Mayor Bill de Blasio said on CNN that Rahami, of New Jersey, "could be armed and dangerous."

"We know a lot more than we did just 24 hours ago. It's certainly leaning more in the direction that this was a specific act of terror," he said on ABC's "Good Morning America."

Twenty-nine people were hurt when the bomb exploded in the upmarket Chelsea neighborhood on Saturday night, damaging buildings, shattering glass and sending shrapnel flying.

A second bomb was uncovered by police four blocks away and defused safely, before being sent to the FBI in Virginia for forensic examination.

Both bombs were pressure cookers filled with shrapnel and made with flip phones, Christmas lights and explosive compound, The New York Times reported late Sunday, citing law enforcement officials.