Officers searching for a 65-year-old man gone missing found a gruesome surprise inside a fish tank in the man’s San Francisco home, police announced Tuesday.

The San Francisco Police Department announced Tuesday that they found a headless corpse inside the fish tank of Brian Egg’s residence on August 15 after homicide investigators went to his home and thoroughly searched his residence.

One of Egg’s relatives called the police on August 7 to report Egg missing, prompting the investigation into his whereabouts.

Egg’s neighbor, Scott Free, told the San Francisco Chronicle he suspected something was amiss in June when he stopped seeing Egg outside his home.

Free contacted the police to perform a welfare check on Egg when he noticed two strangers answering his neighbor’s door. When officers visited the home, the two men told them Egg was out on vacation.

The neighbor contacted the police again on August 14 when he noticed a “private crime-scene clean-up crew” stationed outside the home.

Responding officers arrested one individual at the scene and found suspicious odors and cleaning products in their initial search of the residence. Upon further search of the home, police discovered the headless torso.

Authorities arrested Lance Silva, 39, and Robert McCaffrey, 52, on suspicion of homicide, theft, fraud, identity theft, and elder abuse and booked them into jail. The San Francisco Attorney’s Office has not yet filed charges against the men pending the outcome of the ongoing investigation.

The San Francisco Medical Examiner’s Office took custody of the remains and is investigating the identity of the corpse. Authorities say they have not yet been able to confirm the remains are of the missing man because the body is badly decomposed.