The Patna zoo was closed on Tuesday "until further orders" after strains of avian influenza virus were found in six dead peacocks, Forest officials said.
Morning walkers and Christmas picnickers were in for a disappointment as they found the gates of the 'Sanjay Gandhi Jaivik Udyan' shut with notices affixed on the walls.
According to D K Shukla, the Principal Chief Conservator of Forests, Bihar, samples of the dead peacocks were sent to Kolkata and Bhopal for tests which confirmed the presence of H5N1 virus.
"We are not sure how the peacocks contracted the virus. Birds from outside tend to fly inside the sprawling campus. That could be a possible reason but that is a matter of investigation," Mr Shukla said.
"Although not fatal, the virus spreads rapidly and the decision to temporarily shut down the zoo was taken to minimise the possibility of catching the infection. The zoo is being thoroughly sanitised and experts would examine the campus after five days. Only after it is certified that it was safe for people, would the zoo be again thrown open for visitors," he made it clear.
Last week outbreak of the bird flu was confirmed in some villages of Munger district, about 200 km Patna, where culling of birds had been ordered by the administration.