Indonesia's health ministry says a three-year-old boy with symptoms of bird flu has died, days after the virus killed his sister.

A health ministry official says the boy died Tuesday at a hospital in the West Java city of Bandung. Medical tests are being carried out to see if the boy was infected with the H5N1 strain of bird flu. Samples from the two dead siblings have been sent to a World Health Organization laboratory in Hong Kong for more testing.

The toddler's 13-year-old sister died Saturday, and a 15-year-old sister is being tested for the virus. The official says the three siblings may have contracted avian flu through contact with dead chickens.

If they are confirmed to have died of bird flu, Indonesia's death toll from the disease will rise to 14.