ALLIANCE, Ohio —  A northeast Ohio farmer was attacked by a cow and died a day later of a fractured skull suffered when his head hit the ground, authorities said.

The cow charged Steven Walker, 55, on Monday and knocked him down inside a barn on his farm in Lexington Township, said Rick Walters, a Stark County coroner's investigator.

Walker was pronounced dead Tuesday in the intensive care unit of Mercy Medical Center in nearby Canton.

Investigators plan to interview Walker's 8- and 13-year-old grandsons who witnessed the attack, Walters said.

The cow might have become agitated as Walker moved one of her calves.