VIDEO: Petaluma mom searching for Good Samaritan who returned her purse

PETALUMA, Calif. (KGO) -- A Petaluma mother wants to thank a mystery Good Samaritan who found her purse and returned it to her home on Halloween night.

Katrina Brown was out trick-or-treating with her family Wednesday night when she realized she had lost her purse.

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She thought she had left it at a playground, but when she and her husband retraced their steps, they were not able to find it.

Dejected, they returned home and proceeded to cancel her credit cards. Then they decided to look at their home security system to see how many trick or treaters had visited their home while they were away.

That's when they got their Halloween "treat": video of a man holding Brown's purse.

"In addition to some trick or treaters, there was also a man, ringing our doorbell, holding my purse,"

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Brown told ABC7 News, "When we didn't answer, he put it in our mailbox, which is a closed mailbox. So we wouldn't have seen it when we came home."

Sure enough, when she went to the mailbox, the purse was there with everything still inside -- including a necklace given to her as a teenager.

Touched by the kindness of this stranger, she posted the video on social media, hoping someone would recognize the Good Samaritan so that she can say thank you.

If you know this person, send ABC7 News a message on Facebook or tweet at us with the #ABC7now.