Police discovered 1 billion won ($904,000) in suspicious cases originally thought to contain bombs at a department store in Seoul on Wednesday.

At 9:02 a.m. the police received a 112 call reporting two suspicious looking cases that might contain explosive material from a storage facility employee. The Yeongdeungpo Police Station responded to the call on the tenth floor of a department store with some 20 investigators and a police SWAT team. After evacuating the building and securing the location, police discovered two 270 cubic centimeter cases, roughly the size of a small microwave.

The police bomb squad opened the cases and found 10,000 won bills equal to 200 million won, and 50,000 won bills equal to 800 million won.

According to police officials, the cases were filed to be stored until this August.

“The office was about to move soon, but we were unable to contact the owner of the case to ask him to retrieve it,” said an employee at the storage facility.

“I thought it might have contained explosive material so I called it in,” he said.

Police suspect that an individual or company may have made the “black money”― money obtained through illegal means ― and are currently working to trace the owner of the cases.

By Robert Lee (rjmlee@heraldcorp.com)