PLYMOUTH (CBS) – A missing Plymouth boy has been found safe and a man in custody after an Amber Alert was issued Thursday afternoon.

Investigators say it all began at the Indianhead campground in Plymouth. That’s where police say 36-year-old Arthur Moniz got into an argument with his wife and took off with a four year old boy believed to be his son.

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Police reported that Moniz made statements that he would harm himself and the child.

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That triggered the alert, with the word going out to all departments. About an hour after the alert, Moniz was arrested in the town of Marion on Route 195.

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The boy was found with Moniz and is safe. A child fitting the description of the boy was brought into Plymouth police headquarters Thursday night.