(KRON) — A man is accused of committing an unprovoked attack against an elderly victim who was walking along Whitman Street in Hayward, Alameda County prosecutors said.

James Lambert, 23, allegedly stabbed the 81-year-old victim, Francisco Gonzalez, eight times, according to the District Attorney’s Office.

“Witnesses reported that Lambert stabbed the elderly man eight times in the head and proceeded to strike him with a metal pipe while he lay on the ground,” the District Attorney’s Office wrote.

The August 17 assault was finally halted when an off-duty security guard intervened.

Gonzalez was rushed to Eden Medical Center, where he remained in critical condition on Tuesday. 

Prosecutors filed charges including assault with a deadly weapon, elder abuse, and great bodily injury.

District Attorney Pamela Price said, “This case presents extraordinary circumstances — a senseless and brutal attack on a vulnerable victim. Anyone who commits acts of violence against vulnerable individuals in Alameda County will be held accountable.”

If convicted, Lambert will face up to 14 years in prison.