The two men, former co-workers, apparently had a verbal altercation seven months ago that was never resolved, according to police.
The 47-year-old victim encountered his former co-worker in the 800 block of Seventh Street shortly before 8 a.m. Thursday.
The suspect then allegedly struck the man on the back of the head with a hammer, leaving him in critical but stable condition, according to police.
The suspect, described as a man between 30 and 35 years old, left the scene before officers arrived and had not been located as of this morning, police said.
