Authorities have identified a man wanted in connection with a bomb which exploded in the Chelsea neighbourhood of Manhattan, New York and a pipe bomb which exploded in Seaside Park, New Jersey.
Ahmad Khan Rahami, 28, was named by the NYPD as a wanted man.
An FBI poster warned he could be “armed and dangerous”.
It also described him as around five foot six and weighing approximately 200 pounds. It said that he was born in Afghanistan.
A mobile alert has been sent out asking New York residents to dial 911 if they see Rahami.
The news comes after five more suspected explosive devices have been discovered at a New Jersey train station following a blast in New York that injured 29 people over the weekend.
The mayor of Elizabeth, New Jersey, said one of five devices found in a backpack near a train station exploded while a bomb squad robot was attempting to disarm it, the Associated Press reported.
According to NBC News, an address was being searched in Elizabeth, New Jersey, in direct connection with Rahami.
Christian Bollwage said that the device exploded shortly after 12.30am (5.30am UK time) on Monday. The FBI was leading the investigation and working to disarm the other four devices.
Bollwage said to expect more detonations.
There were no reports of injuries.
The latest findings comes after a weekend of incidents including bomb explosions in New York and New Jersey , as well as a mass stabbing in Minnesota.
The New Jersey discoveries bring the total number of suspected or exploded devices to eight.
Here’s what we know so far:
An explosion in Manhattan, New York, injured 29 people on Saturday night.
A pressure-cooker bomb packed with shrapnel exploded in the Chelsea neighbourhood at about 9pm local time (1am UK time).
The explosive device went off on 23rd Street between Sixth and Seventh Avenues Saturday evening, an area of the city that is teeming with nightlife on the weekends.
The BBC cited reports which said that both were pressure cooker bombs, which also featured fairy lights and mobile phones as detonators.
Authorities said the Manhattan bomb contained residue of an explosive often used for target practice that can be picked up in many sporting goods stores, according to the Associated Press.
All those who were injured in the incident have since been released from hospital.
Governor Andrew Cuomo said at least 1,000 extra officers and the National Guard had been mobilised to monitor the city’s subway system.
Five people are being questioned over the incident.
FBI officers pulled over a car in Brooklyn on Sunday evening.
The Associated Press reported that FBI spokeswoman Kelly Langmesser said “a vehicle of interest in the investigation” of the Manhattan explosion was stopped. She said no one has been charged.
On Saturday, a pipe bomb also exploded on the route of a charity race in Seaside Park, New Jersey.
No one was injured in the incident.
Two more were recovered along the route of a 5K charity race, authorities said.
There is some suggestion of “foreign connection”.
The Guardian reported that New York Governor Andrew Cuomo said there was a possible foreign connection behind the Manhattan blast.
He had earlier said there was no such link, although added the act of blowing up a bomb in a crowded area of Manhattan “is obviously an act of terrorism”, according to Reuters.
No international group has yet claimed responsibility.
Sky News reported New York mayor Bill de Blasio said: “We’re going to be very careful and patient to get to the full truth here.
“We have more work to do to be able to say what kind of motivation was behind this.
“Was it a political motivation? A personal motivation? What was it? We do not know that yet.”
There has also been a mass stabbing in a mall in the state of Minnesota.
Nine people were injured in the incident when a man, who was shot dead by police, attacked a number of people in St Cloud.
The so-called Islamic State terror group claimed the perpetrator was their “soldier”.