(KRON) — A few days after the discovery of a 94-year-old Santa Rosa man who had died “with no signs of trauma or foul play,” new evidence suggested it was an “intentional killing,” the Sonoma County Sheriff’s Office announced on Saturday. The man’s son-in-law has been taken into custody on suspicion of murder.

The deceased, identified by authorities as Sy Van Nguyen, was reported unresponsive on August 11 by his son-in-law, 71-year-old Khanh Trong Tran from Santa Rosa. Emergency responders were called to a residence on the 5800 block of River Road, where they confirmed Nguyen was dead.

“At that time, there were no signs of trauma or foul play, and his body was released to the family,” the sheriff’s office wrote.

On Friday, authorities said deputies received evidence that Nguyen’s death was not natural. An arrest warrant was obtained for Tran.

Tran was located on Saturday inside a vehicle in the 1700 block of Marlow Road and arrested for murder. He remains in custody without bail.