(Montgomery Advertiser) -- Ethan, the baby Indian rhinoceros who made a splash with his arrival to the Montgomery Zoo, has died.
Ethan was the first of his species to be born in the U.S. as result of artificial insemination.
Zooofficials said the death of the 4-month-old rhinoceros was "sudden andunexpected" and that what caused his death is unknown.
A necropsy will be performed to determine the cause of death, said Sarah McKemey, a public relations director for the zoo.
McKemey said nothing obvious was wrong with the rhinoceros prior to his death Friday.
"It is a shock and a loss to us for it to be so sudden and unexpected," McKemey said.
The rhinoceros was named after Ethan Gilman, a boy who was held hostage in an underground bunker near Midland City in January.
Ethan made national news early on, with the "Today" show filming at the Montgomery Zoo for a story on Ethan's milestone birth.
The Montgomery Zoo worked in concert with the Cincinnati Zoo to make the birth possible.
Thesperm was collected from Himal, a male rhino at the Montgomery Zoo, toimpregnate the female Jeta after the two proved too aggressive towardeach other to mate, according to Montgomery Advertiser archives.
Montgomery Zoo staff monitored the roughly 15-month pregnancy and reported afterward that the birth went well.
TheIndian rhinoceros is an endangered species, and Ethan's birth was seenas a sign that artificial insemination could be a valuable tool tomanage the remaining population, according to an article on theCincinnati Zoo's website.