Two men have been charged in connection with the shooting and killing of a husband and wife — both of whom had obtained the rank of colonel in the Army — in the front yard of their home in Springfield, Fairfax County police said Thursday.

D’Angelo Strand, 19, and Ronnie Keandre Marshall, 20, were taken into custody on two counts each of second-degree murder and firearms violations Thursday, following a manhunt that stretched across Fairfax County and the District of Columbia area.

Police identified the victims of Wednesday morning’s shooting as Edward McDaniel Jr., 55, an Army doctor, and Brenda McDaniel, 63, a retired Army colonel and nurse. Their son and another person were at the home when the shooting occurred, police said.

Fairfax County Police Chief Kevin Davis said at a news conference Thursday evening that the motive for the slayings was a dispute, but its exact nature was under investigation. He said the two men charged worked with a relative of the victims but declined to say where.

“We’ve lost two brave, dedicated, lifelong servants to our community . . . and for what?” Davis said. “That’s what’s got us shaking our heads.”

Fairfax County police put out a plea for the public’s help late Wednesday in locating a light-colored Nissan that was seen leaving the scene of the shooting in the Newington Forest neighborhood.

Police said that car was spotted shortly after 7:20 a.m. Thursday at a business in Lorton. Officers arrived and the operator of the vehicle, Strand, of Fort Washington, was taken into custody, police said. The car was seized and is being searched for evidence.

Shortly after 2 p.m., Fairfax County police officers and U.S. marshals spotted Marshall near the intersection of Janna Lee Avenue and Richmond Highway in Fairfax County and took him into custody, police said.

Both suspects are being held at the Fairfax County jail. Neither man was listed in court records yet, so it could not be determined whether they had attorneys. The gun used in the slayings has not been located, police said.

The shooting occurred in the 8000 block of Flint Street around 9:20 a.m. Wednesday, police said. Davis said Wednesday that the McDaniels were gunned down at “point-blank range” and called the killing “in cold blood.”

Davis said Thursday the action that led to the killings began Monday when one of the suspects arrested in the shooting came to the McDaniels’ house. There was a dispute and police were called for an attempted burglary. That incident was under investigation when the slayings occurred.

Edward McDaniel was a doctor of internal medicine at Fort Belvoir Community Hospital, where he was also the director of executive medicine, Army officials said. He had served in the Army since 1995.

Felice McDaniel, his mother, said he had served two stints overseas in Iraq and was scheduled to retire from the Army in November, although he planned to continue working as a doctor.

She said her son was inspired to go into medicine after a high school friend suffered from mental illness. She said Edward grew up in Los Angeles and recounted how as a child he would ask her what she wanted when he got his allowance.

“They loved their country. They loved their service. They loved the people who were their patients,” Felice McDaniel said.

Lennie Enzel, a retired colonel with the Army Nurse Corps and Brenda McDaniel’s superior when she was assigned to William Beaumont Army Medical Center in El Paso, wrote in a Facebook message to The Post that Brenda was an accomplished medical professional, who was selected to the prestigious post of White House nurse during the Clinton administration.

“She was one of the brightest, kindest, most professional Army Nurses with whom I ever had the honor to serve as evidenced by her tour as a White House Nurse,” Enzel wrote.

Army officials said Brenda McDaniel served in the Army from 1983 to 2009 and retired as a colonel.

Army officials said her military awards included the Legion of Merit, which recognizes “exceptionally meritorious conduct in the performance of outstanding services and achievements.” Her awards also indicated at least two deployments overseas.

The Washington Post’s Dan Lamothe and Julie Tate contributed to this report.