The FBI informed Washington lawmakers Thursday that a pipe bomb was found in a short-term rental where the man who drove into a New Orleans crowd on New Year’s morning had been staying.

A Congressional source familiar with the call between the FBI and the House Committee on Homeland Security told Scripps News that investigators also found improvised explosive devices inside coolers on Bourbon Street. The coolers were reportedly purchased at a Walmart ahead of the attack.

Authorities initially stated that they believed Shamsud-Din Jabbar did not act alone when he crashed into a crowd on New Year's morning, killing 14 people. However, on Thursday, they said new evidence shows that he was the sole perpetrator of the attack. Jabbar was killed in a shootout with police immediately after driving into the crowd.

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The FBI stated that the truck used in the attack had an ISIS flag attached. Investigators told lawmakers that while the attacker pledged allegiance to ISIS, there's no evidence he communicated with ISIS operatives.

Jabbar, an Army veteran, posted five Facebook updates on the morning of the attack, according to the FBI. President Joe Biden said on Wednesday that the attacker's post stated that he was inspired by ISIS and had a desire to kill. The FBI told lawmakers that it had no prior knowledge of Jabbar potentially planning an attack.

Lawmakers were also briefed on the blast in Las Vegas that happened after the attack in New Orleans. They were told there are no links between the incidents despite some similarities. Both men served in the U.S. military and they both rented vehicles from the Turo app.

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