Two masked men attempted to break in to a currency exchange office in Gamla Stan around 11:30am on Wednesday.
"They tried both a hammer and an axe," Stockholm policeman Albin Näverberg told news agency TT. "The two black-clad people took off on a moped."
Less than a half hour after the botched robbery attempt, a fire broke out in a vehicle tunnel in the Slussen junction south of Gamla Stan.
Police at the scene of the fire. Photo: Tobias Röstlund/TT
The fire was quickly extinguished, but police said it was caused by a burning moped and that they suspected the two events were linked.
Police have sectioned off parts of Gamla Stan and Slussen and have begun a search for the two masked perpetrators.
On Tuesday night an exchange office in Farsta, southern Stockholm, was also robbed. The thieves reportedly backed up their car to the office and then lit the vehicle on fire.