Residents in the northern Dutch town of Purmerend have been advised to take umbrellas out at night after a spate of attacks by an owl.
Dozens of residents have suffered head injuries over the past three weeks at the claws of the rogue European eagle owl.
Two runners were attacked on Tuesday, with one requiring stitches for five separate head wounds.
The European eagle owl's usual prey are small mammals and birds.
One of the sites of the attacks has been a home for the disabled.
Liselotte de Bruijn, a spokeswoman for the home, told the AFP news agency that residents and workers had suffered at least 15 separate attacks by the nocturnal bird, which remains at large.
"During the day there's no problem, but at night we now only venture outside armed with umbrellas, helmets and hats, anything really, to protect ourselves," said Ms de Bruijn.
Dutch bank Rabobank has donated umbrellas to the home, and a spokesman for the company told local broadcaster RTVNH that it intended to send a falconer.
The Dutch Owl Foundation says the animal's unusual behaviour may be the result of being reared in captivity and associating humans with food, or it may simply be that the owl has heightened hormone levels as the breeding season begins.
Purmerend council advised residents against attempting to capture the owl.
"These procedures can still take some time," a statement said. "Meanwhile, we are advising people to stay away from the owl."
The European eagle owl is one of the world's largest owl species, with a wing-span of up to 1.8m (6ft) and weight up to 3kg (7lbs).