The offices of the Express newspaper on the south side of Blackfriars Bridge were raided by intruders on Sunday night.
Security guards at Ludgate House called Southwark police at 10.03pm on Sunday night after they were unable to prevent raiders entering the Blackfriars Road building.
Reports suggest that the intruders jumped over security barriers and headed to the first floor where they stole computer hardware.
Southwark CID's burglary squad is investigating the raid.
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