WASHINGTON — Three men have been arrested and charged with first-degree murder in the fatal shooting of a Silver Spring man that police say the three arranged to buy marijuana from.

Montgomery County police said Wednesday they arrested 21-year-old Re’Quan Kasim Hopson of Arlington, Virginia; 19-year-old Oliver Waltz Farley, 19 of Arlington; and Brian Anthony Mackall, 20, of Suitland, Maryland.

All three men have been charged with first-degree murder in the July 19 shooting death of 20-year-old Jon-Christian Kemachet-Webster.

Police said the three men showed up to Kemachet-Webster’s home in the Forest Glen area of Silver Spring to buy “a large quantity of marijuana.” Kemachet-Webster invited Farley and Mackall upstairs to his bedroom while Hopson waited in a car parked on nearby Belvedere Boulevard, police said.

At some point, Kemachet-Webster was shot upstairs and both Farley and Mackall fled the home, according to authorities. Police said Mackall got back into the getaway car driven by Hopson, and Farley called an Uber.

Montgomery County police interviewed Hopson the next day in Arlington County where he was being held on an unrelated offense. During the interview, he told police he drove the two to other men to Kemachat-Webster’s house before the shooting.

D.C. police arrested Farley later that afternoon at his job in Northwest D.C., and Mackall on July 24. All three men are awaiting extradition to Montgomery County.