After nearly two weeks of DDoS attacks on various anti-piracy law firms and organizations such as the RIAA and MPAA, Operation Payback is still ongoing. In a possibly connected event, a few hours ago the office of the law firm Dunlap, Grubb & Weaver was evacuated by the police after a bomb threat was received. The firm is responsible for suing thousands of BitTorrent users in the United States in recent months.

What started off as a DDoS attack on the Indian anti-piracy outfit Aiplex Software has evolved into a global assault on more than a dozen organizations involved in anti-piracy campaigns. Aside from attempts to take down the websites of these organizations, many outfits also received numerous prank calls and ‘free’ pizza.

After having attacked the RIAA, MPAA, IFPI, BSA, ACS:LAW and many others, attention shifted towards the US law firm Dunlap, Grubb & Weaver this week. The firm, which started thousands of lawsuits against BitTorrent users under the name US Copyright Group (USCG) this year, is best known for pursuing alleged downloaders of the Oscar-winning movie The Hurt Locker.

Two days ago a group of Anonymous/4chan users called for a DDoS attack on the website of the law firm under the flag of ‘Operation Payback’. Minutes later it was taken down together with their email server. Although the site slowly recovered after a few hours, the trouble for the Leesburg-based law firm were far from over.

Thursday afternoon an email containing a bomb threat was sent to the law firm, whose employees contacted the police. In a swift response from the local police, members from the Loudoun County Sheriff’s Office and the Loudoun County Fire Marshall’s Office evacuated the building.

Several dogs trained in detecting explosives were brought in, but after a thorough sweep of the office no explosive devices were found. After the building was cleared detectives remained on the scene and the police said they will investigate the threat further.

Police spokesman Chris Jones said that the content of the bomb threat email was vague and that no specific reasons for targeting the law firm were given. However, considering the previous DDoS attack on the firm and the prank calls other anti-piracy outfits received, the sender of the email could conceivably be connected to (or inspired by) Operation Payback.

Earlier this week TorrentFreak spoke to one of the people connected to the (DDoS) operation to find out why Dunlap, Grubb & Weaver was included as a target. “They’re all anti-piracy lawyers,” was the non-disguising answer we got. “Think of Dunlap, Grubb & Weaver as of ACS:Law, but in the USA,” Anonymous commented, linking the Leesburg firm to the UK lawyers whose emails ended up on the streets after a DDoS attack.

According to the police report, no direct link between Dunlap, Grubb & Weaver’s anti-piracy efforts and the bomb threat has been made yet. Leesburg Police Department is offering a cash reward to anyone who can help solve the case. People are encouraged to report leads to the police by calling (703) 771-4500. Anonymous calls can be placed at (703) 443-TIPS.