New York officials have identified a suspect wanted for questioning over Saturday’s blast in the Chelsea area in which 29 people were injured.

The man has been identified as Ahmad Khan Rahami, 28, a naturalised US citizen from Afghanistan.

The New York Police Department (NYPD) has released a photograph.

Early on Monday, a backpack containing up to five devices exploded in Elizabeth, New Jersey when a bomb disposal robot tried to deactivate it.

Investigators have warned the suspect, whose last known address was in Elizabeth should be considered “armed and dangerous”.

“Anyone who sees this individual or knows anything about him or his whereabouts needs to call it in right away,” New York Mayor Bill de Blasio said on CNN.

Both the bomb that went off in New York and a device found nearby were shrapnel-filled pressure cookers, according to US media.

It is not clear who was behind the devices found in New Jersey, at the railway station in Elizabeth.