Investigators say that the New Orleans truck attacker had a transmitter they believe would have set off bombs he planted at two other spots in the French Quarter, but responding police killed him before he could activate it.

Shamsud-Din Jabbar, a US-born Army veteran, killed 14 people and injured 35 more early New Year’s morning when he drove around a police barricade on Bourbon Street and drove down the sidewalk. He got out of his rented truck and opened fire on police officers, who promptly shot him dead, after crashing the truck.

The FBI said that Jabbar left his first homemade bomb in a cooler at Bourbon Street and St. Peters Street just before 2 a.m. Wednesday, about an hour and 15 minutes before the ramming attack, the Times-Picayune reported. “Unknowing Bourbon Street visitors” moved that cooler a block away to Orleans Street, investigators said.

Jabbar set the second bomb, in a “bucket-style cooler,” at Bourbon and Toulouse Streets shortly before 2:30 a.m., the FBI said.

Local police initially said they believed he had help setting those bombs, but the FBI said after viewing surveillance footage that the people seen were curious onlookers unconnected with the killer.

Investigators said there were also homemade bombs in the truck along with the transmitter.

“We believe that the transmitter would have functioned and would have worked were it not for the actions of those New Orleans police officers,” FBI Special Agent in Charge Lyonel Myrthil told reporters.

The New Orleans police officers responded quickly after the crash to kill Jabbar, who was wearing a ballistics vest and headgear.