An employee at a Maryland countertop business opened fire on five co-workers on Wednesday morning, killing three of them, and then drove to Delaware and shot a former colleague at a car dealership, the authorities said.

Police departments along Interstate 95 from Maryland to New Jersey conducted a widespread manhunt for the gunman, identified by the authorities as Radee Labeeb Prince, 37, who escaped officers during a brief chase after the second shooting, in Wilmington, Del.

About 10 hours after the first shooting, the authorities announced that Mr. Prince had been captured in Newark, Del. Other details were not immediately available.