Residents at a local village in the outskirts of Nairobi on Tuesday night killed a total of six lions as human-wildlife conflict escalates in the East African nation.

Kenya Wildlife Services (KWS) confirmed the six beasts were speared to death by residents at Oloika area in Kitengela, Kajiado County, about 30 km south of Nairobi.

KWS Corporate Affairs Manager Paul Udoto said they have launched investigations to ascertain the cause of the deaths and also dispatched rangers and a veterinary capture teams to search for the lions.

"The killing is a big loss to the economy given that lions enjoy an iconic status as one of the 'Big Five' which are a big draw for tourists who visit Kenya," Udoto said in a statement issued in Nairobi on Wednesday.

The "Big Five" refers to five kinds of big wild animals in Kenya, including lions, leopards, rhinos, buffaloes and elephants.

Wildlife authorities have cited human-wildlife conflict as one of the major causes of declining number of lions and elephants in Kenya.

The experts said carnivores like lions still attack livestock and this in turn leads to retaliation by the humans. "This is normally carried out in form of poisoning, spearing and even shooting," one wildlife ranger told Xinhua on Wednesday.

KWS has listed elephants, lions, wild dogs, leopards, cheetah, hyenas, Sitatunga, Tana crested mangabey, and Tana red colobus monkeys as some of the most endangered wildlife species in Kenya.

Udoto that two adult lionesses, two sub adults and two cubs had strayed from the Nairobi National Park and entered a pen where the sheep and goats were locked for the night at a local village early on Wednesday and killed the four goats.

"KWS rangers responded to a community report on the stray lions which had strayed from Nairobi National Park and spent the night with them dealing with the problem. The teams are still on site," he said.

Udoto said while KWS investigating teams were still on site the residents killed the beasts from the Nairobi National Park which is seasonal park where herbivores stray out and lions pursue them during rainy seasons.

"In the pursuit lions encounter livestock. While outside the park, the lions occasionally kill livestock from community bomas," he said.

But residents claimed the owner of the home had sent out a distress call promoting them to surround the home for five hours. They said two of the lions managed to escape while one person was injured after the lion bit him in the arm.

"KWS would like to strongly discourage the public any killing of lions and other wildlife as this is criminal," Udoto said.

Instead, communities should alert KWS officers nearest to them about any problem animals. Besides KWS offices spread across the country, the public can report to 24-hour hotlines.

According to Udoto, KWS works with community human wildlife conflict resolution committees and elders in ensuring that people and their property are protected from destruction by wildlife the same way wildlife is protected.

The East African nation has been losing 100 lions a year for the past 7 years, leaving the country with just 2000 of its famous big cats, meaning that the country could have no wild lions at all in 20 years.

Conservationists have blamed habitat destruction, disease and conflict with humans for the lion population decline.

The number of elephants has reduced from a high of 160,000 in 1970s to below 30,000. KWS said between the 1970s and 1980s Kenya lost over 80 per cent of her elephants, mainly due to intensive poaching of elephants for ivory.

Also affected are the Black Rhinos whose number declined from 20,000 in 1970 to current 577 in 2011.