This story is part of a reporting collaboration between NBC News and the Virginian-Pilot newspaper.
A Navy SEAL instructor has been temporarily removed from training duties after a sailor died during a swimming exercise last week in California, a command spokesman said Saturday.
The announcement comes a day after a report by NBC News and the Virginian-Pilot newspaper raised questions about the circumstances leading to the sailor's death, contradicting the official narrative released earlier by the Navy.
Numerous sources told the newspaper that other SEAL students had witnessed an instructor hold Seaman James Derek Lovelace under water immediately prior to his death on May 6.
The incident happened during the first week of the infamously grueling Basic Underwater Demolition/SEALs training, or BUD/S, at Naval Amphibious Base Coronado in California.
The preliminary findings of an autopsy by the San Diego County Medical Examiner's Office indicate Lovelace drowned, though the investigation of cause of death is ongoing. The Naval Criminal Investigative Service is investigating.
"While the investigation is ongoing, the instructor involved has been assigned duties apart from directly training students for the time being," Navy spokesman Lt. Trevor Davids said Saturday in a statement. "As the investigation progresses and details become clear, his Commanding Officer will reassess his status."
Davids was unable to say whether the instructor was removed immediately after the death or following the NBC News report.
The Navy confirmed Lovelace's death on Tuesday, four days after his death, only after NBC News and The Pilot asked about it. At that time, a spokesman said safety observers outside the pool noticed Lovelace "having difficulty" during a routine and not particularly high-intensity drill "and withdrew him from the exercise."
He was taken to a San Diego hospital, where he was pronounced dead.
The Navy's initial account did not describe any role an instructor may have played in the moments leading up to Lovelace's death.
The instructor's temporary removal Saturday was first reported Saturday by the Washington Post, which identified the sailor as an enlisted petty officer first class who joined the Navy in 2008 and has served at SEAL units based in both San Diego and Virginia Beach. The instructor had deployed to Afghanistan at least twice, the Post reported.
According to more than a half-dozen sources who've spoken to The Pilot — none of whom are eyewitnesses, but who include two family members of SEAL students who were present during the incident and a former SEAL who's coaching a student through the same course — Lovelace had been held underwater before passing out.
Unlike what was initially described by the Navy, the sources say the drill involved physical harassment of trainees by instructors in the water, intended to test their ability to stay afloat under stress.
It wasn't a "drown proofing" drill, as was initially reported, but a more intense exercise known as "combat tread," according to three of the sources. During "combat tread," students swim in camouflage uniforms while instructors grab at them in the water.
Lovelace "was hands-on with the instructor," one source said. "The instructor kept physically and verbally harassing him."
Another wrote in an email: "The event was witnessed by multiple trainees and was captured on video."
Cmdr. Jason Salata, a spokesman for Naval Special Warfare Command, said in a statement Friday that Naval Special Warfare Command is "fully cooperating" with the NCIS investigation and a separate Navy safety investigation into the training death.
"It would be premature to discuss any details until those investigations are complete," Salata wrote, declining to specifically address the specifics of events leading up to the training death.
Lovelace joined the Navy in November, after walking away from a baseball scholarship to pursue his dream of becoming a Navy SEAL, family members said. His funeral was held Friday in Florida.