Officers were called to the 800 block of Elm Street at about 1 AM.
When they arrived they found a large group of people outside a house where the man was threatening his girlfriend.
Investigators say an officer told the man repeatedly to drop the cinder block.
Police say the man ignored the officer and continued to threaten to hit his girlfriend with the cinder block.
At that point investigators say the officer opened fire, wounding the man twice.
The suspect is in the hospital in critical but stable condition.
No one else was injured. The officer was evaluated at the hospital and released.
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