Police in the New Jersey city of Linden had received a call about a man sleeping in the doorway of a local business.
When officers responded, one recognised him from a photograph of a man wanted for questioning over a series of explosive devices found in New Jersey and New York.
Linden Police Captain James Sarnicki says when the officers approached the man, he produced a weapon.
"The officer then said show me your hands, the person went to the side of his body, pulled out a handgun and fired a round at the officer, striking him in the abdomen."
The officer was wearing a bullet-proof vest.
The man also shot the other officer through the windshield of a patrol car but both police escaped serious injury.
Captain Sarnicki describes how the shooter was finally apprehended.
"The gentleman did get up and started walking down the street in a westerly direction. I am told from monitoring radio transmission that he was discharging his weapon, possibly at passing vehicles. I don't know who he was shooting at, but at some point our officers responded, returned fire and he was taken down."
Captain Sarnicki says the man was conscious as he was taken to hospital and turned over to the FBI.
Earlier, New York police had released a photo of Amhad Khan Rahami - a 28 year old Afghan-born American who lives in Elizabeth, New Jersey.
In addition to a blast in New York City that injured 29 people, he was also wanted for questioning about other devices that exploded in New Jersey without hurting anyone.
The motive behind the bombings remains unclear but New York City Mayor Bill de Blasio says there's an apparent link to terrorism.
"Based on the information we have now we have every reason to believe this was an act of terror. We will be going into some detail and there is still a long investigation ahead, but now we have, as I said every reason to believe this was an act of terror."
Mr de Blasio also acknowledged there may be an international connection to the cases.
But William Swenney, from the FBI's New York Field Office, says there's no evidence of a terrorist cell in the city.
"The investigation is ongoing, so as we develop more information we continue to go, but I have no indication that there is a cell operating here."
The explosions came days before world leaders gathered at the United Nations in New York for the annual General Assembly.
In his first remarks about the attacks, US President Barack Obama has urged Americans not to succumb to fear.
"Even as we have to be vigilant and aggressive, both in preventing senseless acts of violence but also making sure that we find those who carry out such acts and bring them to justice, we all have a role to play as citizens in making sure that we don't succumb to that fear."
His comments were echoed by Democratic US presidential nominee Hillary Clinton.
But while condemning what she called "the twisted ideology of terrorists", she claims groups like IS have been using her Republican rival Donald Trump as a recruiting tool.
"We know that a lot of the rhetoric we've heard from Donald Trump has been seized on by terrorists, in particular ISIS, because they are looking to make this into a war against Islam. They want to use that to recruit more fighters to their cause by turning it into a religious conflict."
During a campaign rally in Florida Mr Trump has called Ahmad Khan Rahami an "evil thug".
Mr Trump has bemoaned that the suspect will now receive what he calls "amazing medical care" and "an outstanding lawyer".
"He will be given a fully modern and updated hospital room. And he'll probably even have room service knowing the way our country is. His case will go through the various court systems for years, and in the end people will forget and his punishment will not be what it once would have been. What a sad situation. We must have speedy but fair trials and we must deliver a just and very harsh punishment to these people."
