A federal police office was taken into custody today after shootings in suburban Washington shopping centres that left two people dead and two others wounded.
Authorities said they had taken into custody Eulalio Tordil, a 62-year-old officer in the Department of Homeland Security's Federal Protective Service, which protects US government facilities.
Police in Montgomery County, Maryland, outside the US capital, made the announcement on Twitter without offering further details after a manhunt that lasted several hours.
In the morning hours, gunfire broke out at the Westfield Montgomery mall in Bethesda, with one man killed and two people wounded.
A second shooting later at a supermarket in nearby Aspen Hill, Maryland left one woman dead.
Tordil had also been sought in today's shooting death of his wife at a school in Prince George's County, Maryland, on the eve of the two incidents in adjacent Montgomery County.
"This continues to be a very active investigation," Montgomery County Police Captain Paul Starks told reporters before Tordil's capture.
"We're still looking at the possibility that these shootings here (in Bethesda) and the shooting in Aspen Hill are related (and) were committed by the same suspect."
Schools in the vicinity were briefly asked to keep children in place "out of an abundance of caution," the official said. The schools later decided to proceed with normal dismissal.
The incidents occurred in some of the same areas hit by the so-called "Beltway Sniper" in 2002 that prompted a lengthy manhunt and resulted in 17 deaths before a suspect was caught.