India, Jan. 23 -- Six samples collected from Delhi zoo earlier this week tested negative for bird flu, officials said on Friday, days after a brown fish owl that was found dead in its enclosure, was diagnosed with a strain of the infection.

Ramesh Pandey, director, National Zoological Park in Delhi said that while the zoo has not reported any fresh case of the flu, safety protocols have not been relaxed.

"All six samples, including those of the four birds whose enclosures were close to the owl that died of the virus, returned negative on Thursday. However, safety, surveillance and sanitation work will continue, and all protocols and guidelines issued by the Central Zoo Authority (CZA) of the Union ministry of environment forests and cli...