Gunman who killed officer, wounded 3 others allegedly searched online for 'area events where there are crowds'

A gunman who allegedly killed a North Dakota police officer and wounded three others made online searches for "explosive ammo," "kill fast," "mass shooting events" and "area events where there are crowds," authorities said.

The night before the July 14 attack in Fargo, the suspect, 37-year-old Mohamad Barakat, allegedly looked up an article called "Thousands enjoy first day of downtown Fargo street fair," authorities announced Friday.

Barakat, a Fargo resident, allegedly opened fire at the scene of a traffic collision, gunning down Fargo police officer Jake Wallin and wounding three others -- two police officers and a 25-year-old civilian, police said.

Another officer at the scene, who was "dramatically outgunned," shot Barakat, who died from his injuries, authorities said.

No motive is known, said Matt Schneider, U.S. attorney for the District of North Dakota.

"Why did this senseless violence happen? What could possibly motivate someone to ambush young officers in the line of duty?" Schneider said at a news conference Friday. "How could murderous chaos, and this type of evil, arise on a familiar street in Fargo, North Dakota?"

Barakat was armed with multiple semi-automatic long rifles and semi-automatic handguns, as well as gasoline canisters, propane tanks with explosives, and 1,800 rounds of ammunition, North Dakota Attorney General Drew Wrigley said at the news conference. More weapons were recovered at the suspect's home, Wrigley said.

Barakat allegedly used a .223-caliber rifle in the shooting, and his rapid, automatic fire was "made possible because of what is known as a binary trigger," Wrigley said.

"Everything you hit, you'll hit twice because you got the binary trigger," he said.

Barakat was allegedly "putting the finishing touches on his shooting skills in the last hours before this assault," officials said.

The funeral for Wallin, 23, will be held on Saturday.