JACKSON, Miss. » An attorney for the family of a black man who died following an encounter with a white police officer in a Mississippi town says the cause of death was strangulation.

Chokwe Antar Lumumba told The Associated Press on Thursday that he was present when multiple law enforcement agencies briefed family members of Jonathan Sanders on Tuesday, telling them that he died from "manual asphyxiation," and that the death was a homicide and not an accident.

Sanders died July 8 following a physical encounter with Stonewall Police Officer Kevin Herrington. Sanders was driving a horse and buggy in the town before Herrington stopped him in a residential neighborhood. Lumumba said relatives believe Herrington is at fault in Sanders’ death.

Herrington’s lawyer, Bill Ready Jr., told the AP later Thursday that the 25-year-old officer stopped Sanders on suspicion that he had drugs and that Sanders resisted arrest in a physical struggle.

"There’s always another version of what truly happened," Ready said. "I think we need to all wait until MBI finishes its investigation."

Mississippi Bureau of Investigation spokesman Warren Strain has described the encounter as a physical "altercation."

Lumumba wouldn’t say what agencies briefed the family, but MBI has been leading the inquiry, assisted by the FBI.

"All we can say at this point is the policy of the Department of Public Safety is that we don’t discuss ongoing investigations," Strain wrote in a text to the AP.

Jason Pack, supervisory special agent with the FBI’s Jackson office, also could not confirm the finding.

"As in any case where additional resources might be needed, we’ve offered the FBI’s investigative and forensic capabilities to our partners at the Mississippi Bureau of Investigation, who is the lead in this case," Pack wrote in an email.

Clarke County Coroner Greg Fairchild did not return a call seeking comment. Stonewall Police Chief Michael Street said Thursday that he was unaware of the finding.

Authorities have confirmed that there are multiple witnesses, including Herrington’s wife, who was in the patrol car, and Rachel Williams, a resident who works as a jail guard in neighboring Lauderdale County. Lumumba’s law partner, C.J. Lawrence, is representing Williams.

The autopsy finding doesn’t necessarily mean Herrington committed a crime, and he hasn’t been charged. Lumumba said he believes that there is enough evidence to show that Herrington committed a crime, and urged that Herrington be indicted. However, he said that he has not yet asked for authorities to conduct a probable cause hearing, required before police officers and some other public employees can be arrested in Mississippi.

Clarke County District Attorney Bilbo Mitchell has said the case, like other deaths where a police officer is involved, will be presented to a grand jury. The next grand jury in Clarke County is scheduled to begin Aug. 31, Mitchell has said, although he said it might be possible to recall grand jurors who met in February. Mitchell could not be reached for comment Thursday.

Lumumba and residents say Sanders, 39, made his living buying, selling and training horses. Lumumba has said Sanders was exercising a horse after 10 p.m. July 8 in preparation for an upcoming rodeo. Sanders had served time in prison for selling cocaine, and had been arrested for cocaine possession earlier this year. Authorities were also seeking the forfeiture of a vehicle and cash following the 2015 arrest.

Sanders’ funeral is scheduled Saturday in nearby Quitman, with a protest rally scheduled for Sunday in Stonewall, which is about 20 miles south of Meridian.