UK police have started replacing ads on websites that provide access to pirated or copyright infringing material with warnings to web users that the site is on a watch list — and a call for them to close the browser page in question. The initiative, called Operation Creative, is being carried out by the City of London Police’s Police Intellectual Property Crime Unit (PIPCU) and follows a call by the unit, back in April, for advertisers to get behind a plan to tackle IP related crime by helping disrupt piracy sites’ access to ad revenue.