From Halopedia, the Halo wiki
In October 2553, Svenson and Oscar Squad were conducting a training exercise against a Ferret team led by Veta Lopis at the UNSC Recreational Facility 6055-NA-A on Neos Atlantis. After Olivia-G291 was drugged by investigative reporter, Spencer Hume, Veta suspected Oscar Squad was behind it. After Svenson attempted to get between Olivia and Veta, Veta accused him of dosing Olivia, hyperextended his elbow, and punched him in the kidney. Later, Svenson saw Mark-G313 and Ash-G099 while they were getting rid of Hume's body but soon lost them around a corner. After losing the pair, he found blood and, following standard procedure, Svenson intended to clean up the scene but when he returned he found it already done. Svenson later reported what he saw to Serin Osman, who took him to see Veta's team. After Veta and Svenson traded suspicions for a while, he denied Hume and the server who had collaborated with the reporter were a part of his squad. He then fervently denied dosing Olivia with nicothiotal, claiming that he would never use it during a training exercise. After discussing what happened in the hallway, Veta accused Svenson of using this incident as a way to get into the Ferrets' safe house. Svenson denied that was the case, but Osman sent him out to wait with her escorts.