A pair of 20-pound dumbbells and a knife were the murder weapons used in the deaths of an elderly Pikesville couple, Baltimore County police said Wednesday.

Police charged the couple's grandson, 31-year-old Matthew Long, with two counts of first-degree murder, according to Elise Armacost, Baltimore County Public Safety spokeswoman. Long is being held in an Oklahoma City detention center.

"Baltimore County homicide detectives have interviewed Long, who willingly provided a statement," Armacost said in an email.

Long was found unresponsive on Sept. 11 in a Weatherford, Okla., hotel room. Next to him was an unsigned note that said, "I am sorry for everything. Please forgive me."

The couple, Vaughn Pepper, 87, and Marjorie Pepper, 85, were found dead on Sept. 10 in their Sudbrook Park home in the 800 block of Olmstead Road. They died of blunt- and sharp-force trauma, police said.

Police believe the couple died on Sept. 8, Armacost said. Police checked on the couple after they were alerted by neighbors.

The knife that was allegedly used in their deaths was not recovered, police said.

Authorities said Long drove his grandparents' 2009 Mercury Grand Marquis to Oklahoma. Once there, he checked into the Travel Inn hotel and overdosed on prescription medicines. He was found unresponsive and transported to an Oklahoma City hospital, which discharged him Tuesday.

Extradition proceedings have not begun, Armacost said.

ywenger@baltsun.com

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