LONDON (Reuters) — They survive on fresh blood drained from the neck of a living cow, they often run for days and nights on end to find water and their shoes are made from car tyres cut up and strapped to their feet.

So running the London Marathon should be no problem for six Maasai warriors who have come to Britain from their village of Eluai in northern Tanzania as part of a campaign to raise money to find a vital water source.

"Back at home we sometimes run for five or six days, day and night," Isaya, a young warrior clothed in a red robe and adorned with traditional beaded jewellery, told Reuters in an interview. "Twenty-six miles not far."

He and his fellow warriors, all between 20 and 25 years old, expect to reach the finish line of Sunday's race within four and a half hours.

They will run in traditional dress — a red "shuka" blanket toga and car-tyre sandals — carrying spears and shields showing their running numbers, and will sing and dance along the 26.2 mile route through the British capital.

"And we will do the whole marathon with no water," Isaya adds. "We often travel for many days, eating only twice a day, and we have no water.

"If we have no milk or meat, we cut the cow's neck and let out the blood to drink. If I drink enough blood — maybe two or three litres — it gives me a lot of energy and I can go for days without food or water."

The Maasai warriors, whose role is to protect and help provide for their people, hope to raise enough money to find and access a fresh water source for their community — something they say could cost up to £ 60,000 ($120,000).

An estimated 500,000 to one million Maasai inhabit scattered and remote villages across northern Tanzania and southern Kenya, living a semi-nomadic existence.

But years of drought in the region around Eluai, where these six warriors live with their elders and children, is killing their cattle and threatening their way of life with disease and famine.

Two thirds of the children born in Eluai die before they reach the age of five.

"It is a large village which has a very bad lack of water. We have only one small dam and the water from it runs out very quickly," said Isaya. "It is affecting our people. Our children are dying.

"We are infected with disease from water which is dark and dirty. We sometimes have years with no rain."

Paul Martin, an expedition leader with the Greenforce charity which has been working with the Maasai since 2005, said ground surveys of the area around Eluai had found an underground water source which could offer the Maasai a lifeline.

"It's an enormously difficult and expensive procedure, but it's so desperately needed that we have to make sure we get something out of there, even if we have to go down to depths of 100 metres," he told Reuters.

Martin suspects the sight of thousands of London marathon runners taking two sips of water from a bottle at each mile and throwing the rest away is likely to horrify the Maasai runners, but says it will only fuel their determination.

"The Maasai are a proud people ... If they achieve this, they will return to their village as heroes," he said.

And Isaya has no doubt he and his fellow runners will do it.

"The finish line for us is not at the end of the race, it is when we can turn on a tap in Eluai," he said. "I really believe that can happen."

They will run wearing shoes made from car tyres, carrying their sticks and shields, and chant Masai songs as they go around the 26-mile course on April 13.

Isaya said in a blog supporting their cause: "Our elders told us that we can do it because we have been running all over for killing a lion and herding cattle.

"We can help them by getting them clean water so right now all of us we are training very hard."

"We are training three days a week and we run for about 20km. My younger brother, Nguvu, he has a very good speed and i run after him but he doesn't listen to me!

"Another guy called Taiko, we run after him but no one catches him!

"On another day we ran again and we were acting that we are going to kill a lion so everyone had to run faster to catch a lion soon as possible and that day we all had a good training and we won together!"

The Masai runners have been warned that in London they will also have to deal carefully with a strange and difficult species: the capital's workers.

You may be surprised by the number of people that there are as they all seem to be rushing around everywhere," reads a travel guide written by Greenforce, a British charity working with the village.

"Even though some may look like they have a frown on their face, they are friendly people — many of them just work in offices, jobs they don't enjoy, and so they do not smile as much as they should."

The Masai men — who are considered warriors once they have tracked and run down a male lion before killing it — have been given the guide to warn them of the many dangers and peculiar traditions of British life.

The effect on alcohol on Britons is also described. "Many people drink alcohol in England. They do so at bars, at homes, at homes or at clubs — the English equivalent to a Masai party. When people drink they (seem) sillier or different. I am sure you have seen it with the Greenforce volunteers."

www.maasaimarathon.org