BRESCIA, Italy (AP) — Two German men went on trial Wednesday on manslaughter charges in connection with a boat collision in Italy’s Lake Garda that killed two Italians who were also out on the lake that night.

Patrick Kassen, who was allegedly at the helm of the Germans’ motorboat during the June 19 incident, turned himself into Italian authorities in July and has been under house arrest in Italy. He was in court on Wednesday, but his co-defendant, who has remained free in Germany, was not.

The hearing in the Brescia tribunal was adjourned after about an hour.

Investigators believe the Germans’ motorboat slammed into the smaller vessel of Umberto Garzarella and Greta Nedrotti, allegedly after the two tourists from Munich had been out drinking. Garzarella was found dead in the boat while Nedrotti’s body was found two days later during a police search of the lake.

The Germans are charged with manslaughter and leaving the scene of an emergency. Kassen has been quoted by Italian media as saying he didn’t realize the boats had collided. The tourists returned to Germany after the incident but Kassen presented himself to authorities after learning an arrest warrant had been issued.

Relatives of Garzarella and Nedrotti were in court for Wednesday’s hearing.

“I have nothing to say because I have a lot to say, I am now going to entrust the Italian Justice,” said Garzarella’s father, Enzo Garzarella.