US police are hunting for an “armed and dangerous” man suspected of shooting five people in Maryland and one person in Delaware on Wednesday morning.
The gunman opened fire at around 08:58 (12:58 GMT) at a countertop business about 25 miles (40km) north of the city of Baltimore, officials said.
The suspect, 37-year-old Radee Labeeb Prince, reportedly worked as a machine operator at the firm.
Police say he later drove to Delaware and shot a man at a used-car lot.
Local schools and the set of the Netflix series House of Cards, which is about a mile away, were placed on lockdown as police searched the area.
Three people died in the shooting at the Emmorton Business Park near Baltimore.
Two other victims were left critically injured and are in hospital with gunshot wounds to the head, said Maryland Governor Larry Hogan.
Investigators are treating the first shooting as a workplace violence incident, according to Dave Fitz, a spokesman for the Baltimore FBI field office.
The suspect fled the scene in a black vehicle with a Delaware licence plate, officials said.
Mr Prince is also suspected of shooting a sixth person, more than 50 miles away, at the second-hand car business in Wilmington, Delaware, police told NBC Philadelphia.
A man at the car dealership was shot three times, the networks reports, and has been transported to hospital.
Police have not yet released any more information about the shooting in Wilmington, where the suspect is said to have family.
Harford County Sheriff Jeffrey Gahler said all five victims in Maryland were employees of the Edgewood business, Advanced Granite Solutions, but none of the victims have been identified.
“This does appear to be a targeted attack, limited to that business,” the sheriff said, adding that the victims were apparently shot with a handgun.
Advanced Granite Solutions owner Barak Caba told the AP news agency the suspect had been employed with the company for four months.
It is not clear if he was still working there at the time of the shooting.
Governor Hogan said he had activated the state’s fugitive apprehension team, and two helicopters were deployed in the manhunt.