SANTA CLARA, Cal. (CNN) — Police in California are calling on the public to help catch the person who beat a 91-year-old man with a rock.

The heartbreaking story gets worse. Police say the man was visiting his wife’s grave like he does everyday when he was attacked.

Other visitors at the cemetery saw the beating and called 911.

Authorities have released a sketch that they hope will identify the suspect.

“It is completely unacceptable and we are at the point where we’re challenging the public to help us identify and locate the person responsible for this,” said Captain Wahid Kazem from Santa Clara Police.

There’s no word on the victim’s condition, but police say some of his possessions were stolen during the attack.