Crowley did not enter a plea. His relationship to the child — and the identity of the boy’s mother — were still not clear.

He told investigators he had been in a car crash and left the baby behind because the child was “very heavy,” prosecutors said in an affidavit obtained by NBC News.

The baby, who was left alone for at least seven hours, was discovered in the middle of the night on Sunday, officials in Missoula have said. He was in good condition, according to the Missoula County Sheriff’s Office.