The war crimes case of Special Operations Chief Edward Gallagher just got more complicated as the Navy is expanding its investigation to SEAL Team 6 operators.

According to warrant documents and emails leaked to the Navy Times, the Naval Criminal Investigative Service (NCIS) is trying to determine if Chief Gallagher colluded with SEALs from the Naval Special Warfare Development Group (DEVGRU), another title forSEAL Team 6. According to the documents and electronic messages, Chief Gallagher allegedly encouraged DEVGRU operators to obstruct justice by coercing SEALs familiar with Chief Gallagher’s actions to remain silent. Furthermore, Chief Gallagher appears to have asked them to retaliate against anyone who spoke to the NCIS agents.

Since the whole affair began last fall, NCIS agents have been tracking electronic devices across the SEAL community to determine the veracity of the war crimes accusations. A number of SEAL Team 7 operators have been granted transactional immunity, which protects a witness from prosecution for the offense or offenses involved in a case, in exchange for testifying against Chief Gallagher.

Since the very early stages of the Global War on Terror, DEVGRU operators have been involved in war crimes cases. From subjecting the heads of dead enemies to “canoeing” (splitting the skull by shooting a round at the upper forehead), to chopping heads with hatchets, to intentionally calling airstrikes on buildings packed with civilians in Iraq or Afghanistan, there has been much controversy around the Tier 1 Navy unit.

Phillip Stackhouse, one of Chief Gallagher’s defense attorneys, said to the Navy Times that “Chief Gallagher has proclaimed his innocence and demanded speedy trial since the day he was unjustly thrown into pretrial confinement. While this case has been continued once due to significant evidence being delivered on essentially the eve of trial, Chief Gallagher has never wavered in his desire to get to trial as soon as possible.”

Chief Gallagher is charged with stabbing to death with a hunting knife an underage Islamic State prisoner, shooting at unarmed civilians with his sniper rifle, and threatening his teammates to remain silent about his actions, as well as calling false coordinates for an airstrike in an attempt to destroy a mosque. He had also been accused of wrongly conducting a re-enlistment ceremony beside a dead jihadist, but a Navy judge ruled that action didn’t violate the Uniform Code of Military Justice.

The trial has been postponed until May 28 because the defense attorneys didn’t have sufficient time to go over newfound evidence prosecutors used.