Man suspected of killing three workmates linked to a second shooting

A gunman shot five of his co-workers at a US office park in the state of Maryland on Wednesday, killing three of them and setting off a manhunt, authorities said.

The gunman was linked to a later shooting at a used car dealership in Delaware about 55 miles away.

At least one victim was targeted, authorities said, but the extent of their injuries was not released.

Authorities said it was not clear why the man they identified as 37-year-old Radee Labeeb Prince arrived at work as scheduled and opened fire with a handgun on five of his colleagues.

Harford County, Maryland, Sheriff Jeffrey Gahler said Prince shot his victims about 9am and fled the Emmorton Business Park in Edgewood, eluding deputies who arrived in four minutes.

Kevin Doyle of Thornhill Properties said he was getting tools from his vehicle when he heard screaming and saw three men running from the office park.

The men told him someone was shooting and he asked if they had called 911.

They said no, even though, Mr Doyle said, they had phones in their hands.

“I think they were just so scared, they didn’t (call 911). They had a look of terror,” he said.

The victims and the suspect worked for Advanced Granite Solutions, the owner of the company said.

Prince has been an employee for four months, working as a machine operator, owner Barak Caba said.

The wounded were in critical condition with gunshot wounds to the head, according to Maryland governor Larry Hogan, who spoke at an unrelated event.

He said authorities in helicopters and on the ground were searching for Prince, who may be driving a black 2008 GMC Acadia with the Delaware licence plate PC64273.

“The killer remains on the loose,” Mr Hogan said.

Prince was fired from another job earlier this year after he attacked a co-worker, according to The Baltimore Sun.

A former co-worker sought a restraining order against Prince in February, saying he had punched another employee and threatened employees.

“I felt very threatened because he is a big guy and very aggressive on me,” the co-worker said in the application for the restraining order.

The man said Prince did not get physical with him, but wrote: “I do not want to wait until he will.”

A Harford County District Court judge denied the order.