From Halopedia, the Halo wiki
After the Flood outbreak on Installation 04, the rest of his unit were apparently devoured by the parasite. He managed to survive, and sent a Priority Alpha distress call through the transmitter of the Bumblebee escape pod Lima Foxtrot Alpha 19. The transmission mostly consisted of the panicked private asking for help. Near the end of the transmission, movement started appearing outside the pod, and the private apparently committed suicide with his M6C pistol.
The transmission was later retrieved by the Office of Naval Intelligence, and analyzed in a highly classified report as a part of the ongoing investigation of the Flood threat. The private's name, along with most other details, was redacted from the report.
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