Helena Olsson of the Parken Zoo told Sweden's The Local that zoo wardens reacted swiftly to the commotion but were too late to save the majority of the flock. Five other flamingoes sustained injuries.
"The anteater is not a meat eater, unless you consider ants meat, but when it feels threatened, it will defend itself," Olsson said.
She said the anteater apparently panicked when the birds cackled and flapped their wings after it broke into their compound.
"The birds are very frail and the anteater is very strong," she said.
The five injured birds are expected to make a full recovery.