OTTAWA -- Ontario's Special Investigations Unit (SIU) says three Ottawa police officers are the subject of an investigation into the death of 23-year-old man following a police raid earlier this month, but it's not yet known if they will cooperate with the investigation.

Anthony Aust died Oct. 7 after falling from the window of an apartment on Jasmine Crescent when police officers burst into the family's apartment with guns drawn and set off a smoke grenade during an investigation.

Video of the raid was captured on camera and sent to CTV News by a member of the Aust family.

The SIU invokes its mandate to investigate any interaction involving police when there has been death, serious injury or an allegation of sexual assault.

In a newly released update, the SIU says three officers will be the subject of the investigation, while nine other officers are designated as witnesses.

However, police officers in Ontario cannot be legally compelled to participate in SIU investigations. The SIU says it has yet to hear whether the officers involved in the Oct. 7 incident will agree to be interviewed.

"Pursuant to Ontario Regulation 267/10 of the Police Services Act, subject officers cannot be legally compelled to present themselves for an interview with the SIU and they do not have to submit their notes to the SIU. The SIU has not yet heard back whether the officers will agree to interviews," the police watchdog said.

Two of the nine witness officers have been interviewed. The remaining interviews are expected to take place this week, the SIU said. Four civilian witnesses have also been interviewed.

The SIU is urging anyone who may have information about this investigation to contact the lead investigator at 1-800-787-8529. The Unit is also urging anyone who may have any video evidence related to this incident to upload that video through the SIU website.