Authorities have filed federal charges against Ahmad Khan Rahami, the sole suspect in the weekend bombings in Manhattan and New Jersey.
The charges include use of a weapon of mass destruction, bombing a public place and destruction of property. Rahami previously had been charged in New Jersey in connection with the shootout that led to his arrest Monday.
The criminal complaint, filed in the U.S. District Court for the Southern District of New York, details why investigators are convinced that Rahami is behind Saturday's bombings.
The government claims that police found 12 fingerprints on the bomb that detonated on West 27th Street in Manhattan and all of them match Rahami. The complaint notes that investigators also found prints on the explosives found in Elizabeth, N.J., and they match Rahami.
According to investigators, Rahami allegedly began buying materials to build the bombs earlier this summer. Rahami used the nickname "ahmad rahimi" to buy citric acid, a circuit board and a fireworks firing system on the Internet.
Those materials, investigators, say were shipped to a business address close to Rahami's house in Perth Amboy, N.J., and they are also the same materials used to build the bombs in New York and New Jersey.
Investigators also found that one of the cellphones used as the timing device on one bomb was registered to one of Rahami's relatives.
The most stunning piece of evidence mentioned in the complaint, however, is a video investigators found on a cellphone. According to a description of the video, it shows Rahami in a backyard "igniting incendiary material in a cylindrical container."
"Partially buried in the ground is a small, black cylindrical object," the complaint notes. "A fuse is lit and the object ignites; the Video depicts the lighting of the fuse, a loud noise and flames, followed by billowing smoke and laughter. Rahami then enters the frame and is seen picking up the cylindrical container."
The charging documents do not give any background on Rahami. But a law enforcement official tells NPR that Rahami's father, Mohammad R. Rahami, had called New Jersey police in 2014 over a dispute involving his son. He later retracted his complaint.
When these types of complaints come in, they usually go into the FBI's Guardian Threat Tracking System, which prompts a limited level of investigation and surveillance.
In a statement, the FBI said that it "conducted internal database reviews, interagency checks, and multiple interviews, none of which revealed ties to terrorism."
According to The New York Times, which first reported the FBI contact, Mohammad Rahami told local police he suspected his son might be involved in terrorism.
The newspaper interviewed the father, who said:
" 'Two years ago I go to the F.B.I. because my son was doing really bad, O.K.?' he said. 'But they check almost two months, they say, 'He's O.K., he's clean, he's not a terrorist.' I say O.K.'
"He added: 'Now they say he is a terrorist. I say O.K.' "
According to court documents, prosecutors wanted to charge Rahami over a domestic dispute. The documents show prosecutors presented a grand jury with aggravated assault charges, arguing that Rahami allegedly stabbed a relative named Nasim Rahami in the leg. The grand jury, however, found there was not enough evidence to indict Rahami.
Talking to reporters outside his home, Mohammad R. Rahami said he had called police on his son because he "stabbed my son" and "hit my wife."
"I put him in jail two years ago," the elder Rahami said.
Ahmad Khan Rahami was taken into custody again Monday after a short but intense manhunt, and was charged later that day with five counts of attempted murder of a law enforcement officer and two counts related to possession of a weapon.
Tuesday's charges are related to a pressure-cooker bomb that went off Saturday night in the Chelsea neighborhood of Manhattan that injured dozens, a pipe bomb explosion that morning in Seaside Park, N.J., and a collection of pipe bombs discovered Sunday at a train station in Elizabeth, N.J.
The investigation is now focused on motive.
The criminal complaint gives a hint of what that might be. Authorities said they found diary entries allegedly written by Rahami that refer to calls for jihad at home if one is unable to travel. The entries also laud radical cleric Anwar al-Awlaki, Nidal Hassan, who shot and killed 13 people at Fort Hood, Texas, and "brother Osama Bin Laden."