The Kenya Wildlife Service says residents on the outskirts of Nairobi speared to death six lions after the carnivores killed four goats from their herd.

KWS said Wednesday that two adult lionesses, two younger lions and two cubs were killed overnight by a mob wielding spears.

KWS said the killings are a big loss to Kenya's economy, given the number of tourists who travel to Kenya to see big game. The lions had strayed outside of Nairobi National Park in search of food when they killed the goats.

Kenya has been losing 100 lions a year for the last seven years, leaving the country with 2,000 of the big cats. Killing lions in Kenya is a crime, but Kenyans who lose livestock to lions frequently retaliate by killing lions.