Twenty-pound dumbbells and a knife were the weapons used to kill longtime Sudbrook Park residents Vaughn and Marjorie Pepper.
According to Baltimore County police, the dumbbells have been recovered, but the knife has not.
The Peppers died of blunt- and sharp-force trauma, according to a news release Wednesday.
Police also say that Matthew Long, 31, their grandson and suspect in their suspicious deaths, was found unconscious in a motel room in Weatherford, OK, by Oklahoma police.
"Oklahoma authorities found a note in the room saying, "I'm sorry,'" the release states.
Long is being held in Weatherford, OK, "on a Baltimore County warrant charging him with two counts of first-degree murder," it states.
Baltimore County police found the Peppers' bodies inside their Olmstead Road Home on Sept. 10 after a neighbor and out-of-state relative requested that they check on them.
Homicide detectives believe the Peppers died Sept. 8.
Long, who was living with the couple, was missing.
Baltimore County homicide detectives went to Oklahoma where Long was hospitalized, then announced he was a suspect on Sept. 14, the day of the Peppers' funeral and burial in Secretary, Dorchester County.
"Baltimore County homicide detectives have interviewed Long, who willingly provided a statement. Extradition proceedings have not begun," the release states.
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