Wildlife rangers in the Kenyan capital said Friday they were hunting for two lions who left Nairobi's national park and went into "highly populated" areas.
Kenya Wildlife Service (KWS) issued an appeal, "for help to get two lionesses that strayed from the Nairobi National Park."
"Lions are dangerous wild animals. Avoid provoking the lions by confronting them," said KWS spokesman Paul Udoto.
At least two lionesses are reported to have late Thursday left the park, spread over 117 square kilometres (45 square miles) where buffalo and rhino roam just seven kilometres from the bustling high-rise city centre.
It is not the first time lions have prowled into Nairobi.
The big cats find themselves under growing pressure as one of Africa's fastest growing cities creeps onto ancient migration routes and hunting grounds.
Sometimes the lions are killed by livestock farmers protecting their herds, other times they prowl leafy gardens giving residents a fright.
"These are highly populated areas and that is why we are intensifying the search," Udoto said. "Anyone with information about them should share with us immediately."
Udoto said two lionesses were last sighted around Nairobi's Langata district.
"Our teams comprising veterinary officials have been in Langata looking for the animals," he said.
While the park is fenced in on the city side — some bars even have terraces where one can view animals while enjoying a cold drink — the park is open-sided elsewhere to allow the annual wildlife migration in search of grazing.
But the land is under threat from increasing urbanisation and more intensive agriculture, and the routes used by migrating herds in search of new pastures as well as the carnivores that follow for fresh meat are growing narrower.
Lions are estimated to have declined in number by as much as three-quarters since 1980, and to occupy less than a tenth of their historic range across Africa.