Police say the five males, aged from 15 to 26, were arrested Thursday at their homes across the UK for their alleged involvement in hacking several company websites.

Police say the cyber attacks were carried out by an online group called “Anonymous,” a loose-knit group of activists that has attacked websites of companies that have severed links with WikiLeaks since it began publishing its massive trove of secret US diplomatic cables.

Thursday’s raid was part of a police probe into “Anonymous” that is carried out together with law enforcement agencies in Europe and the US.