MADISON (WKOW) -- Prosecutors filed a first-degree intentional homicide charge against the man accused of attacking and killing his former coworker.

Keith Jones appeared in Dane County Court on Friday for his initial appearance.

Prosecutors say Jones attacked 62-year-old Mark Tiggelaar with a hammer around 2 a.m. on September 20.

The criminal complaint reveals Jones was fired from his security job at Camp Randall Stadium 10 days before the attack. Jones and Tiggelaar had previously worked together and had a fight at work, unrelated to Jones' firing.

Prosecutors detailed the moments leading up to the attack during Friday's hearing.

"Wearing a white hockey mask on his face, he approaches [Tiggelaar] in the lot with a hammer in his right hand and swings at [Tiggelaar]'s head," said the p

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