UK's Metropolitan Police Service (MPS) is investigating both older and recent distributed denial of service (DDoS) attacks orchestrated by Anonymous.
MPS launched its probe into the hacktivist group's actions after receiving complaints from several affected organizations during the last couple of months.
"Earlier this year the Metropolitan police received a number of allegations of denial of service cyber attacks against several companies by a group calling themselves Anonymous.
"We are investigating these criminal allegations and our investigation is ongoing," a statement from New Scotland Yard reads, according to the Guardian.
The complaints are the result of a DDoS campaign known as Operation Payback (O:P). A lot of people might be familiar with Anonymous' recent pro-WikiLeaks attacks against companies like PayPal, Visa, Mastercard or Moneybookers.
However, the group launched Operation Payback at the end of September as a campaign against the entertainment industry and anti-piracy groups.
The attacks began after an Indian company paid by film studios to remove copyrighted information from the Internet, openly admitted to DDoSing torrent websites.
At the beginning of December, when Anonymous changed the O:P goals to fight against WikiLeaks censoring efforts, the DDoS campaign was already two months old.
Amongst its older victims were two UK-based law firms involved in copyright litigation called ACS:Law Solicitors and Davenport Lyons, the London-based Ministry of Sound independent record label and the British Phonographic Industry (BPI) association.
This, however, doesn't mean the Met is not also looking into more recent incidents. "The Metropolitan police service is monitoring the situation relating to recent and ongoing denial of service attacks, and will investigate where appropriate," the MPS said.
The investigation could well result in arrests in UK, especially since the DDoS tool used by Anonymous members, called the Low Orbit Ion Cannon (LOIC), does not hide the IP address of its users.
Two teenagers have already been arrested in the Netherlands for participating in the recent attacks against Visa, Mastercard and the website of the Dutch attorney general's office. A third Anonymous member is suspected to have been detained in Greece.