An investigation has been launched at a funeral directors after an undercover reporter filmed corpses left unrefrigerated and racism against mourners.

Shocking footage due to be broadcast tonight in an ITV documentary shows workers at Gillman Funeral Services, which has branches in Tooting, Balham, Battersea, Norbury, Carshalton and Mitcham.

Filmed by undercover reporter Tom Ellis, who was based at the premises in Tooting, staff are recorded mocking the dead, calling one "scum" because he is a Chelsea supporter and making racist comments.

Corpses were seen being stored without refrigeration, with a staff member even commenting on the smell.

Bingo sessions were organised at care homes as a way to drum up business, and a member of staff admits to exploiting devout communities such as Ghanaian and Jamaican families by offering expensive services.

Funeral Partners Ltd, who took over Gillman, in 2010 have suspended six members of staff, almost a quarter of the workforce.

The internal investigation is taking place across the six branches, including Norbury.

Chief executive Phillip Greenfield said: "Everyone here at Gillman Funeral Service is shocked and disappointed by recent serious allegations of inappropriate behaviour and comments.

"The alleged behaviour of a small number of our 28 staff goes against everything we believe in and everything this company stands for.

"When I heard about these allegations, I immediately launched both an internal investigation and an external enquiry into our procedures, standards and training."

Apologising for distress caused, Mr Greenfield said: "We are investigating what has happened and in the meantime I offer my sincere apology for any distress to families caused by these totally unacceptable incidents.

"We truly value diversity and we do not tolerate racist language or behaviour anywhere in our business. There are no exceptions.

"We thank you for your understanding as we work to resolve these difficult issues."

Exposure: The British Way Of Death is on ITV1 on tonight (September 26) at 10.35pm.