A man accused of attacking an Escondido Army veteran and leaving him in critical condition pleaded not guilty Friday to attempted murder and other charges.

Thomas Caleb Butler, 32, appeared in State Superior Court in Vista following his arrest in connection with the May 20 attack on 69-year-old Kerry Sheron. Butler was charged with attempted murder, elder abuse, making criminal threats, and battery. A judge ordered Butler held without bail for the time being.

Deputy District Attorney Ross Garcia said Sheron suffered severe injuries during what prosecutors described as an unprovoked attack.

“It was a single punch to the jaw,” Garcia said. “The victim then falls to the floor, and there are subsequent hits to the victim’s head area.”

Garcia said Butler faces up to 15 years in prison if convicted.

Authorities have not said what led to the attack or whether Butler and Sheron knew each other.

“It’s unclear at this moment if they knew each other,” Garcia said. “What I can say is that it was an unprovoked attack.”

“The officers and thankfully, the Escondido Police are investigating this thoroughly, and we should have some more answers there soon,” Garcia said.

Sheron’s home is known in the Escondido community for its display of dozens of American flags and banners supporting President Donald Trump. Some people believe the display may have played a role in the attack, though prosecutors declined to speculate on a motive.

An Escondido woman says a man nearly beat her husband to death outside of their home. The Army veteran is now fighting for his life in the hospital. The suspected attacker is being held on attempted murder charges. NBC 7’s Joe Little reports.

Two days after the attack, a steady stream of supporters stopped by Sheron’s home, leaving flowers, balloons and prayers for the Army veteran.

Sheron’s wife said the couple had previously experienced harassment and threats related to the displays outside their home, but said incidents had never turned violent before.

Garcia said the charges against Butler could change if Sheron does not survive his injuries.

This story was originally reported for broadcast by NBC San Diego. AI tools helped convert the story to a digital article, and an NBC San Diego journalist edited the article for publication.