Police said that the security guard, who had just recently begun working with Panaxia, was arrested and placed in custody on the day of the robbery
Police suspect that she provided the thieves with information on where to find the money, Expressen and Aftonbladet report.
“Naturally we are dismayed by this. But until there is proof she will remain innocent in our eyes,” Panaxia’s spokesman Thord Axelsson told Aftonbladet.
The suspect is not reported to have any prior convictions.
Four masked robbers arrived at the cash depot in Stockholm suburb Bromma in the early hours of Wednesday morning. They entered the building using cutting torches, explosives and an aerial platform before making off with an undisclosed sum of money.