GRETNA, La. (AP) — A black suspect who died in a struggle with white deputies last week died of asphyxiation and there was evidence of pressure on his neck, the coroner in a New Orleans suburb said Monday.

Jefferson Parish Coroner Gerry Cvitanovich told reporters at a news conference Monday that the death of Keeven Robinson, 22, was classified as a homicide based on the preliminary autopsy results, which indicated traumatic neck injuries "consistent with compressional asphyxia." He said complete results, including toxicology reports, will take weeks.

"That said, I don't want to delay disclosure regarding the direction in which we're heading from Mr. Robinson's family, the sheriff's department or the media," Cvitanovich said at a joint news conference with Jefferson Parish Sheriff Joe Lopinto.

Lopinto said Cvitanovich told him of the autopsy report Saturday. He said the four deputies involved in the arrest have been read their rights and are cooperating in an investigation that involves his office, state police and the FBI.

"I understand that this investigation will be under a microscope," Lopinto said.

Lopinto declined to immediately identify the deputies. He confirmed they are white. Robinson was black.

Lopinto said it was too early to conclude whether a choke hold was used.

"There's no doubt they used force," Lopinto said. "It's whether the force was excessive."

News outlets in New Orleans reported that authorities had said Robinson was under surveillance by narcotics agents Thursday morning when he noticed the agents approaching at a gas station. He drove away but abandoned his car after crashing into two vehicles. Deputies chased him and caught and handcuffed him in the back yard of a home. Lopinto said he was in possession of heroin. He was unarmed, although there was a gun in the abandoned car.

Among those attending the news conference was Gaylor Spiller of the Jefferson Parish chapter of the NAACP. She said the organization was supporting Robinson's family and keeping an eye on the case, mindful of numerous deaths of black people at the hands of law enforcement officers.

She credited Lopinto and Cvitanovich for being open about the autopsy results and the investigation. "We're her to support all sides," Spiller said. "I just want the truth."