BANGOR — A man who is charged with killing a 6-month-old boy in Millinocket has pleaded not guilty to manslaughter.

Jesse Mackin appeared in court on Friday after being indicted for the death of Larry Lord Jr., the son of his girlfriend.

Mackin, 33, was living with the baby’s mother in Millinocket. The baby died after being brought unresponsive to the hospital in May.

The baby was the son of Anthony Lord, 35, of Houlton, who is accused of kidnapping a woman and killing two men in separate shootings last year in northern Maine.