Gurgaon, Jan 12 (IANS): No bird has been found dead in the Sultanpur National Park, a bird sanctuary on Gurgaon-Farrukhnagar Road, here in the past two days after it was closed for visitors following death of 45 birds, an officials said Monday.

"Though dead birds didn't show signs of an H5N1 infection, we cannot rule out of bird flu. Reports are awaited and expected to come within 10 to 12 days," district forest officer Kulwinder Singh told IANS.

He said: "No fresh death was reported in the last two days. Everything was fine in the park by Friday evening but 45 birds have been found dead Saturday morning. We are examining the CCTV footage installed in the sanctuary."

The birds, mostly Eurasian coots, were found dead inside the sanctuary. Their carcasses were sent to the National Institute of High Security Animal Diseases in Bhopal for avian flu tests.

According to the park management, the deaths were caused by some pesticides and they decided to close the park immediately as a precautionary measure.

"Prima facie, the deaths seem to have happened after the birds ate pesticide infested crops at a nearby field. They move in flocks that is why a group of birds died at once," said a bird expert.

Of the 45 dead birds, 35 were Eurasian coots, eight common moorhen, one Spot-billed duck and one Jungle babbler.

"The birds were buried, taking all precautionary measure with layers of salt and chemicals," said Kulwinder Singh.

He said the park will be opened to visitors only after confirmation that the deaths did not happen due to bird flu.