Court testimony has provided new details in a fatal stabbing involving co-drivers that occurred in California in August.

Truck driver Keith Alexander Forrest, 66, recently appeared in court for a hearing related to a homicide charge filed against him for the death of co-driver Erin Michael Anderson, 39.

Anderson was found dead from knife wounds around 9 a.m. on the morning of August 26 on an I-5 off ramp near Newman, California.

Forrest was arrested without incident at a Love’s truck stop in Santa Nella about an hour after Anderson’s body was discovered, allegedly telling the arresting officers, “Yeah, it’s me you’re looking for.”

Forrest has since asserted that he acted in self-defense.

Reporting from the Modesto Bee on the hearing provides new insight into the events that led up to the fatal stabbing.

According to the outlet, things were tense between the two truckers, who were on the final day of a six day route, when they were contacted by California Highway Patrol (CHP) Officer Marco Rivera.

Rivera said that the two had been arguing about the way that Forrest had parked at a gas station for about an hour by the time that he pulled their truck over for speeding around 8:25 a.m. on August 26.

Rivera attempted to mediate by offering to transport one of the co-drivers to a truck stop, but they refused. Rivera testified that he saw Forrest standing outside of the truck while Anderson threw items out of the truck, but that both men eventually got back in the semi and drove off.

Rivera told the court that he also drove away, traveling five miles south to the Stuhr Road exit on I-5. There, he stopped because of a crowd of bystanders and saw Anderson’s body.

CHP Detective Octavio Martinez also testified that Forrest told him that the argument between the truckers turned physical after Anderson opened the passenger side door by reaching over Forrest. Forrest then says he tried to grab the keys from the ignition. Forrest alleged that Anderson tried to push him out of the truck, then started punching him in the side of the head. Forrest alleged that it was at this point that he stabbed Anderson with a pocketknife.

The two men allegedly fell out of the truck, with Anderson landing on top of Forrest. Forrest said that he stabbed Anderson again. Forrest told police that he then got back in the truck and drove off, leaving Anderson on the ground.

The Modesto Bee reports that two knives were later found in Forrest’s possession. No weapons were found in Anderson’s possession.