NAGPUR: Stung by a BBC documentary questioning India's aggressive protection measures at Kaziranga national park in Assam, the National Tiger Conservation Authority (NTCA) that governs all tiger reserves in the country has imposed a ban on the network and its journalist Justin Rowlatt for five years.As reported by TOI on February 15, BBC's South Asia correspondent Justin Rowlatt's documentary titled `One World: Killing for Conservation' on Kaziranga's rhino conservation methods came in for sharp criticism from the Union environment ministry for being “grossly erroneous“. The documentary claimed forest guards in Kaziranga had been given powers to shoot and kill anyone they think was a threat to rhinos.In a memorandum issued on Monday , NTCA said BBC had failed to submit the documentary to MoEFCC and the MEA for obligatory previewing. It has asked chief wildlife wardens of all tiger range states and field directors of tiger reserves to disallow filming permission to BBC in any of the protected areas for a period of 5 years.