E.R. Fazio was a character cut from Alien early in its production. He was originally going to be the Security Officer aboard the USCSS Nostromo, and was to be the first victim of the fully-grown Alien.
Fazio was originally the sole Security Officer assigned to the Nostromo. After Kane's death from the Chestburster, Dallas ordered Fazio to search the lower levels of the ship for the Alien while the rest of the crew searched the upper decks. While searching through the lower levels, he was attacked and killed by the full-grown Alien. His body, much like Dallas', was never found.
Behind the scenes
The character was cut early in production of the movie, largely due to Ridley Scott feeling that a Security Officer aboard the ship would make it seem like the crew was incompetent, sending their only Security Officer alone to search for the creature that had just killed the Executive Officer.