Nick Gordon had some sort of black fluid foaming out of his mouth when someone called 911, audio from the call reveals.

via TMZ:

The 911 call came in as “cardiac respiratory” on New Year’s Day. As we reported, Nick was rushed to the hospital where he died.

A man claiming to be Nick’s brother said Nick died of an apparent OD, and the “black stuff” could support that conclusion. Black discharge is sometimes related to a “foam cone” that comes out of the mouth and nostrils after an opioid OD.

The medical examiner will conduct an autopsy — possibly Thursday — and the toxicology results should be available in about 3 weeks.

TMZ broke the story … Nick was present when Whitney Houston’s daughter and his girlfriend — Bobbi Kristina — OD’d in a bathtub in 2015. He was found civilly liable for her death and the cops investigated him in connection with her death for years, but he was never charged.