"Caesar Must Die", a black-and-white docu-drama shot in a high-security prison on the outskirts of Rome, won the Golden Bear best picture award at the Berlin film festival on Saturday.

The powerful film, directed by veteran brothers Paolo and Vittorio Taviani, was among the favourites to scoop the coveted honour.

The Tavianis followed a group of convicts, including murderers and "Mafiosi", as they rehearsed for a jail performance of "Julius Caesar".

Critics said the fact that most of the cast was behind bars for between 14 years and life intensified the drama of Shakespeare's tragedy.

The jury grand prix runner-up Silver Bear went to Hungarian drama "Just the Wind", based on the real-life murder of a Roma family.

Christian Petzold took home the best director prize for German Cold War drama "Barbara", which had been many festival goers' tip for the top prize.

Feature film debutante Rachel Mwanza was the popular winner of the best actress award for her performance as a child soldier in the harrowing "War Witch".

"A Royal Affair", based on a real-life 18th century royal scandal in Denmark, scooped two prizes - best actor for Mikkel Boe Folsgaard as the deranged king and best screenplay for co-writers Nikolaj Arcel and Rasmus Heisterberg.

Lutz Reitemeier was awarded the artistic achievement Silver Bear for his cinematography in the epic Chinese period drama "White Deer Plain".

"Sister", about a young boy who steals ski equipment from an upmarket Alpine resort to make ends meet, won a special one-off Silver Bear.