The IPCC said the three arrested were a 50-year-old sergeant who was arrested at work, a 29-year-old Pc arrested at an address in south London and a retired PC aged 48 who was arrested by appointment at a central London police station.
Sean Rigg died from a cardiac arrest at Brixton police station in August 2008 and the inquest jury found that police officers used "unsuitable" force after arresting the 40-year-old schizophrenic for attacking passers-by and police officers in Balham, south London.
More top news
MI5 face mounting pressure over claims the IS executioner 'Jihadi John', named yesterday as a London graduate, was known to them
Labour leader Ed Miliband is due to set out his party's plans on how it would cut tuition fees.
New drug driving laws are to come into effect next week, including laws on some prescribed medications.