From Halopedia, the Halo wiki
Jones was one of the Marines stationed aboard the UNSC Pillar of Autumn and was evacuated with the other personnel on board. Under the command of First Lieutenant Melissa McKay, Jones joined a convoy that was ferrying supplies to Alpha Base. However, Covenant ground forces under the command of Noga 'Putumee soon attacked the convoy using Wraiths, Banshees and Ghosts. Jones was in the fourth Warthog with Sergeant Corly when the vehicle was hit by a Plasma Mortar round from a Wraith. Corly was killed but Jones was thrown free. Once recovered, he discovered that his helmet (with his team mic) was missing; as a result, he could no longer call for a pickup as the supply convoy left him for dead. He retrieved his weapon and some supplies scavenged from the Pillar of Autumn, and then followed his sniper training and climbed to some cover and an elevated firing position in the form of rocks.
Targets soon presented themselves in the forms of two Sangheili, one being Minor Ado 'Mortumee and the other being a Field Master, Noga 'Putumee. His first shot decapitated Ado 'Mortumee, but his second, aimed at 'Putumee, missed as the Field Master back-flipped for cover. The Covenant commander responded by calling down Banshees to locate and kill the human. It is unknown if Jones was killed by the Banshees' attack run, made it back to Alpha Base or was killed by the Flood, or perhaps killed when Spartan-117 detonated the Pillar of Autumn's engines and destroyed Halo. As such, his fate is unknown, but he is almost certainly dead.
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