Knut the polar bear unexpectedly died at the age of four on March 19, 2011 in the Berlin Zoological Garden in Berlin, Germany.

The polar bear was found floating in the pool inside his place, said a spokesman for the Berlin Zoo.

Witnesses said that the bear¡¯s rear left leg began shaking, had short fits, fell backward into the water and died. He drowned before zookeepers could rescue him from the water. About 600 to 700 zoo visitors saw him die.

After examining the bear, it was found that Knut died of epilepsy. Epilepsy is a disorder of central nervous system. It causes loss of consciousness and fits. Significant changes to the brain may have caused the bear¡¯s sudden death, the zoo said.

Knut may have inherited epilepsy from his father Lars. Lars also had epilepsy.

Knut became world famous after he was rejected by his mother after birth. He was raised by zookeepers.