This Hospital Porter was killed by a Weevil which had gone rogue in Cardiff and come up from the sewers. The Weevil was contained on a floor of the hospital by Torchwood with the cover story of a chemical leak to isolate the ward. Gwen Cooper, in an attempt to find out more about Torchwood, broke the seal and was followed by the porter. Believing the Weevil a man in a mask, the porter got close enough to have his throat ripped out.
Gwen later learned that Torchwood had covered his death by retroactively changing the work rotas for the day. They also established a false alibi that he was seen leaving the hospital. This gave him forty-eight hours before his body was pulled out of the docks the next Tuesday night, so he was 'missing' for three days. (TW: Everything Changes)