A filmmaker who was assaulted while hiking with his dog outside Bend died of natural causes and not from the attack, according to autopsy results.

Friends and relatives of Clemens D. Schenk, 69, had believed his death July 30 was caused by an attack he suffered in May in Phil’s Trail complex west of Bend.

Deschutes County District Attorney John Hummel was monitoring the death investigation to possibly bring charges against the assailant, whose identity is not known.

The Oregon medical examiner’s office found a burst aneurysm in Schenk’s brain that was not related to the assault, and was, in the opinion of pathologist Clifford Nelson, the cause of Schenk’s death, according to Hummel.

“He deemed the death to be due to natural causes,” Hummel said Tuesday.

In mid-May, Schenk was struck in the head by a man while walking his dog off-leash with two relatives from Germany. Two and a half months later, Schenk died following a swift downturn in health, and it was suspected for a time by authorities that the punch caused Schenk’s death.