Police in South Africa have confiscated cameras that were filming Nelson Mandela's house.
Colonel Vishnu Naidoo told the BBC that two media groups were being investigated.
He said the cameras were constantly filming the ex-president's residence from a neighbour's house.
Under South African law, it is illegal to film or photograph the houses of presidents and former presidents.
Colonel Naidoo declined to reveal the name of the media groups suspected of placing the cameras.
Qunu is where Mr Mandela, 93, grew up in the Eastern Cape. He has appeared increasingly frail since he retired from public life in 2004.
After leaving prison in 1990 following more than 27 years in jail, he led the African National Congress party to a landslide victory in 1994. He stood down as president in 1999.
