Two suspects have been apprehended in the killings of an active duty service member and his wife, both of whom were military physicians, authorities announced Thursday.

The “brutal” double slayings Wednesday morning took the lives of Army Col. Dr. Edward McDaniel and his wife, Dr. Brenda McDaniel, in Fairfax County, Virginia, just outside of Washington, D.C., said Fairfax County police.

Edward McDaniel, 55, was active duty and Brenda McDaniel, 63, was retired, police said.

The McDaniels were “distinguished military veterans” who were shot dead in “cold blood” in front of their home, Fairfax County Police Chief Kevin Davis said at a news conference Wednesday. Two people were inside the house at the time and survived uninjured, police said.

Ronnie Keandre Marshall, 20, and D’Angelo Strand, 19, have each been charged with two counts of second-degree murder and two counts of use of firearm in commission of felony, Maj. Ed O’Carroll, commander of the department’s major crimes bureau, said at a Thursday evening news conference.

The suspects worked with a relative of the victims and police believe the motive was a “dispute,” Fairfax County Police Chief Kevin Davis said Thursday. Davis said authorities have not determined the specifics of the alleged dispute.

Authorities had responded to the McDaniels’ home on Monday — for a dispute and burglary report — and police said they believe “Monday’s response is directly connected” to the killings.

Police said they believe at least one of the two suspects was at the victims’ home on Monday.

The gun has not been located, police said.