Police on Friday arrested a federal officer suspected in a two-day shooting rampage in the Washington suburbs that killed his wife and two apparent strangers and revived memories of the "Beltway sniper" attacks of 2002.
Three others were wounded in the three separate attacks.
Eulalio Sevilla Tordil, 62, a police officer with the U.S. Department of Homeland Security's Federal Protective Service, was arrested in a doughnut shop near the site of the second of Friday's two shootings, police said.
He had been suspected of killing his wife and shooting a bystander on Thursday in Prince George's County, Maryland.
When two more shootings broke out in neighboring Montgomery County on Friday, investigators turned their attention to Tordil, who had threatened to commit "suicide by cop," police said.
A plainclothes officer spotted Tordil in a Dunkin' Donuts. Police kept him under watch as he walked in and out of stores, but waited until he returned to his car before arresting him, Montgomery County Police Chief Thomas Manger told a news conference.
"We did not want to have a shootout when he was taken into custody," Manger said.
Surrounded by officers with their weapons drawn, Tordil surrendered without a fight after about five minutes, police said.