BELLEVILLE, N.J. (CBSNewYork) — A fedora wearing thief is on the loose in Belleville, and now cops are warning residents about the man they’re calling a rare criminal.

Surveillance video shows a man lurking around a home. Police said he was about to break into in the middle of the night.

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“He had an unusual outfit on. He had a fedora on, and had a mask with eyes cut out, almost like a Halloween costume,” Det. Sgt. John McAloon said.

Cops said the family left their Eugene Place door unlocked on Thursday night, making it an easy target for the thief.

McAloon said the criminal spent 40 minutes in the house, but what’s more unusual is the time of day.

“We don’t get many night time burglaries. It’s a unique breed. When they start coming in at night it’s particularly concerning to us,” he said.

According to police, the homeowner and her two children fell asleep on the basement level futon, and that’s when he grabbed the woman to try to put her in a nearby room. During the chaos, the woman’s 6-year-old son woke up and ran upstairs to alert his grandfather.

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“He woke up, started screaming, ran upstairs, doing what we think prevented something worse from happening,” McAloon said.

The intruder robber ultimately ran off with just $20 from the woman’s purse, and also left a water bottle behind.

“If they got a positive DNA match, that person would be our primary suspect,” McAloon said. “If he’s had a prior arrest it will be on file.”

Some neighbors on the block said it’s a frightening reminder to lock the doors and windows.

“This is terrible, never happens here. I’ve been here 16 years,” one resident said.

Authorities said there will be a police presence on the street in front of the house for at least the next few days.

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Police do not believe the family was targeted.