Linwood Johnson is a suspect in the slaying of Lenny Harris. (Courtesy of Prince George's Coun/COURTESY OF PRINCE GEORGE'S COUN)

The man charged with killing an Alexandria activist was ordered held without bond Wednesday, as Prince George’s County homicide detectives continued their search for other suspects, authorities said.

Linwood Johnson, 49, is charged with the first-degree murder of Lenny Harris, 53, whose remains were pulled from a well in Fort Washington late last week. Harris, who lived with his wife in Del Ray, was known in Alexandria for speaking out for the underprivileged, and he made an unsuccessful run for the City Council in 2007.

Detectives are working to unravel the mystery that began when Harris vanished in September. They have determined that Harris was fatally shot before he was dumped in the well on a vacant property in the 11900 block of Old Fort Road and that those who attacked him had set out to rob him. It remains unclear, however, why he was targeted and what Johnson’s alleged role in the crime was. Police have said the men were “known to each other.”

Efforts to reach Johnson’s family Wednesday were unsuccessful, and a spokeswoman for the Prince George’s State’s Attorney Office said no one came to speak on his behalf at a bond hearing.