21 December 2010 Last updated at 08:34

Audio slideshow: Masai warriors graduate

Kenya's Masai people hold a ceremony for their warriors to become tribal elders only every 10 to 15 years, when there are enough people of the right age group.

But the tradition is under threat as the population becomes more urban and more exposed to outside influences. BBC East Africa correspondent Peter Greste witnessed one of the ceremonies just outside Nairobi, where two of the men taking part told him how important the ceremony is for them.

WARNING: This slideshow contains images of animal slaughter.

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Photography and audio by Peter Greste. Sound recording by Paula Kahumbu.

Slideshow production by Paul Kerley. Publication date 21 December 2010.

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