US attacks: What we know so far

Updated 1556 GMT (2356 HKT) September 19, 2016

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(CNN)The investigation into the weekend attacks in the US is moving fast. Officials have been sifting through evidence retrieved from the scenes of the blasts in New York and New Jersey, a stabbing spree in Minnesota, and a backpack loaded with explosive devices discovered in Elizabeth, N.J.

Security has been stepped up as members of the United Nations General Assembly gather in New York for a summit Monday.
Ahmad Khan Rahami, a man police earlier said they wanted to question in connection to the bombings in New York and New Jersey, is now in custody after a shootout with police in Linden, New Jersey, sources say.
As authorities investigate signs of a possible terror cell, we round up what we know and don't know.

    NEW YORK BLAST AND PRESSURE COOKER DEVICE

    Ahmad Khan Rahami was arrested after a shootout with police on Monday. They were able to identify him through a fingerprint, also the cell phone on the pressure cooker found in New York provided some clues.
    What we know: Twenty-nine people were injured when an explosion went off in the Chelsea neighborhood of New York at around 8:30 p.m. on Saturday. All of those admitted to hospitals had been released.
    Shortly after the blast a few blocks away, investigators also found a pressure cooker with dark-colored wiring connected by silver duct tape to what appeared to be a cellphone, officials said.
    Surveillance footage shows the same man near the explosion, and where the pressure cooker was found.
    On Monday Ahmad Khan Rahami, a 28-year-old US citizen of Afghan descent, was arrested after a shootout with police.
    He was wanted for questioning in connection with the blasts in New York and New Jersey, and the backpack containing explosives in Elizabeth.
      What we don't know: What the motive is behind the blast and whether the perpetrator acted alone or as part of a wider group.
      The pressure cooker device found near the blast site.

      MINNESOTA MALL STABBING

      ISIS claims 'soldier' who stabbed 8 at mall
      ISIS claims 'soldier' who stabbed 8 at mall

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      ISIS claims 'soldier' who stabbed 8 at mall 00:47
      What we know: ISIS said that a man who stabbed nine people at a Minnesota mall on Saturday evening was a "solider of the Islamic state", according to the ISIS-linked news agency Amaq.
      The attacker has been named as 22-year-old Dahir A. Adan, according to two Somali community leaders who are in direct contact with his family.
      He wore a private security company uniform, made a reference to Allah and asked at least one person if they were Muslim before he attacked, according to police and witnesses.
      The stabbings at Crossroads Mall in St. Cloud happened in several stores, and off-duty police officer Jason Falconer has been hailed a "hero" after shooting dead the attacker who lunged at him with a knife.
      Stabbing suspect Dahir A. Adan went to college in St. Cloud and worked for a private security firm, Somali community leaders told CNN.
      What we don't know: CNN cannot independently confirm that ISIS was behind the attack.

      NEW JERSEY CHARITY RUN EXPLOSION

      Explosive goes off in trash can during charity run
      seaside park police presser bomb race sot_00000818

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      Explosive goes off in trash can during charity run 01:30
      What we know: An explosion in a garbage can near a Marine Corps charity run in New Jersey on Saturday is being investigated as a possible terrorist act.
      Ahmad Khan Rahami-- the same man wanted in connection with Saturday's bombing in New York -- has been arrested in connection with the explosion in New Jersey.
      Three pipe-bomb-type devices wired together were found near the boardwalk at the Seaside Park event, said officials, adding that the devices were rudimentary and only one of them detonated.
      No one was injured in the blast -- most likely because registration problems delayed the start of the race, so no one was near the garbage can when the explosion happened.
      The explosion went off in a garbage can.
      What we don't know: Whether it's part of a weekend of co-ordinated attacks.
      Investigators said they found similarities between this device and the bomb that exploded in New York's Chelsea neighborhood Saturday evening, but have not linked the two events at this time.

      ELIZABETH BACKPACK LOADED WITH DEVICES

      FBI Bomb Squad is on scene and continuing the investigation at the train station in Midtown Elizabeth.
      What we know: A backpack containing up to five explosive devices was found in a wastebasket in Elizabeth, New Jersey, around 9.30 p.m. on Sunday.
      The backpack was found outside a neighborhood pub and located about 500 feet from a train trestle, said the city's mayor Chris Bollwage.
      Officers sent in a robot to examine the devices, causing one of them to explode. The remaining four devices will be transferred to the FBI laboratory at Quantico, Virginia, said Bollwage.
      Ahmad Khan Rahami, the man arrested Monday after a shootout in Linden, New Jersey, is also believed to be connected to the pipe bombs found in a backpack, sources said.
      What we don't know: What exactly were these devices? "I don't know what they're made up of," said Bollwage of the package.