The head of the UN’s Independent Investigative Mechanism for Myanmar (IIMM) said Monday that Facebook has not shared evidence of “serious international crimes” relating to its investigation into military abuses in Myanmar.

Nicholas Koumjian, head of the UN body collecting evidence of the most serious international crimes and violations of international law for the purpose of criminal prosecution, told Reuters that Facebook holds information that is “highly relevant and probative of serious international crimes” but has not shared it with the IIMM yet.

Koumjian said, “Unfortunately, to date, the Mechanism has not received any material from Facebook but our discussions continue and I am hopeful that the Mechanism will eventually receive this important evidence.”

A case on the interpretation and application of the Genocide Convention is ongoing before the International Court of Justice (ICJ) over the 2017 military “clearance operation” that led more than 730,000 people to flee to Bangladesh. The 2019 case was instituted by The Gambia. Myanmar denies the charge of genocide and has maintained that its security forces were conducting legitimate operations against Rohingya militants who attacked its border police.

Last week Facebook urged the US District Court for the District of Columbia to reject The Gambia’s request to obtain posts and communications of members of Myanmar’s military and police. It said that acceptance of the request would violate the Electronic Communications Privacy Act of 1986. However, a spokesperson for the company said that it is cooperating with the IIMM.

The company stated that it, “stands against hate and violence, including in Myanmar. … We support action against international crimes and are working with the appropriate authorities as they investigate these issues.”