CHARLESTON COUNTY, S.C. (CBS Local) — A 6-year-old boy who fished out a locked metal safe in South Carolina has solved a mystery that’s older than he is.

Knox Brewer recently took up magnet fishing, where people hunt for ferrous metal objects underwater using a strong magnet.

READ MORE: Invasive Spotted Lanternfly Found in Oakland County; What To Do If You See One

“We got it to help pass the time during the virus,” Knox’s mother, Catherine Brewer, told WCIV.

During a Mother’s Day outing, Knox discovered something sitting at the bottom of Whitney Lake. With the help of a nearby stranger, they fished out a locked metal safe.

When they pried it open, they found several items inside, including “jewelry, a notebook, and a checkbook.”

READ MORE: Woman Found Dead Inside SUV In Northwest Detroit

Knox’s father, Jonathan Brewer, called the police. As it turned out, the safe belonged to a neighbor who said the safe was stolen from her home eight years ago.

“The first thing that she did was just kneel down, hug Knox and thanked him and thanked him for bringing that closure to her,” Jonathan said.

“She got some missing charm bracelet pieces that were still left in there, she said all the expensive stuff was gone but at least she got closure and some of her pieces back,” Catherine said.

Jonathan says the discovery gave Knox a chance to play detective.

MORE NEWS: Lawyer In Whitmer Kidnap Plot Trial Raises Concern About Juror

“He himself wants to one day become a police officer and so he got a lot of fun out of them coming out and investigating, asking questions and trying get to the source,” Jonathan said.