LIVE OAK, Fla. — The Live Oak Walmart Supercenter has been evacuated after a bomb threat was called in Tuesday.

Law enforcement are searching the building to see if anything is out of the ordinary, Sheriff Sam St. John said.

According to St. John, the caller stayed on the phone for nearly 20 minutes with a store manager demanding money be placed on a gift card electronically or he would set off the bomb.

St. John said Homeland Security and the FBI have been notified since the caller allegedly claimed to be a son of Osama bin Laden.

Law enforcement is also trying to locate the caller by tracking his phone number, although St. John said it’s possible the caller was using some kind of software or app to produce that number.