Three wildlife rangers and four poachers died in a fierce gun battle at the weekend close to one of the most important populations of elephants in Kenya.

Conservationists said that heavily armed gangs, some from across the border in lawless Somalia, were continuing to target ivory despite an international ban on the trade.

A team of seven rangers had been following the poachers for a week in the remote Tana River District after a tip-off. Julius Kipngetich, the director of Kenya Wildlife Service, said that the rangers laid an ambush at Idsowe Bridge on Saturday for the poachers, who were heading for Tsavo East National Park.

“At about 1.45am, five heavily armed men appeared and as they were crossing the bridge they were ordered to stop by my men but opened fire and a fierce battle ensued,” he said. “It is unfortunate that we lost three of our rangers and another was injured but we managed to fell four.” Two AK47 rifles, hundreds of rounds of ammunition and two axes were recovered from the scene.

Kenya has long been praised by conservationists for leading the battle against poaching. A ban on hunting and armed patrols have helped elephant numbers to rebound from fewer than 10,000 in the early 1970s to about 30,000 today.

A third of elephants in Kenya live in Tsavo East, but the problem of poaching has never gone away, driven in part by a huge demand for ivory in the Far East. Last year wildlife service officers arrested 14 people and seized 160kg (350lb) of raw ivory, breaking up what rangers believed to be a syndicate smuggling animal products out of Africa.

A recent report by researchers at the University of Washington in Seattle found that up to 5 per cent of African elephants – about 23,000 animals – are being slaughtered for ivory each year.

Dame Daphne Sheldrick, who runs an elephant orphanage outside Nairobi, said that global warming, encroaching human populations and a ready supply of cheap guns were combining to keep the animals under threat. “Whenever there is a country in chaos, like Somalia, where AK47s are cheaply available, then poaching is inevitable,” she said.

Next month, parties to the Convention on International Trade in Endangered Species of Wild Fauna and Flora are due to meet in the Netherlands. Southern African states, where elephant populations are growing, are pushing for a relaxation of the international ban. The move is opposed by Kenya and Mali.

Animal magic

— 1.48m tourists visited Kenya in 2005, mostly to see wildlife

— £462m was contributed to Kenyan income by tourism in 2006

— 70% of tourism revenue is generated by wildlife

— 8% of the country’s land area is covered by national parks

— 14% of tourists in Kenya are British, 15 per cent German

Source: Government of Kenya

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