A world heritage site in northern Senegal that welcomes millions of migratory birds every year is now closed to visitors until further notice, after 750 pelicans were found dead.

The dead birds were found at the weekend and were incinerated as a precaution, Reuters news agency reports

"We took some samples for screening and we hope in the near future to know what caused the death of the pelicans," said Bocar Thiam, the director of Senegal’s parks.

Results are expected by the end of the week, reports RFI.

"You don't hear of avian flu affecting fish-eating birds," Mr Thiam told the French-language broadcaster, apparently ruling out one suspected cause.

Some 100,000 chickens have been culled this month following an outbreak of bird flu at a poultry farm in southern Senegal.