The robbery took place at the junction of Götgatan and Blekingegatan in the Södermalm district. Police were alarmed at 4:19pm.
“Two attackers seem to have carried out some kind of robbery,” police spokesman Björn Engström told news agency TT.
The two attackers forced the guards to hand over their bag, Svenska Dagbladet reported. The pair then made away on a moped.