Dozens of people have been arrested at an army barracks in Kenya after turning up with fake call-up papers, it's been reported.

Authorities say that the 57 were held when they arrived at the Recruits Training School at Moi Barracks in the city of Eldoret along with hundreds of genuine Kenya Defence Forces recruits, Nairobi News reports.

All of those arrested held letters telling them to report there on 31 October following a nationwide army recruitment process, the paper says.

According to Ali Samatar, the local director of criminal investigations, the fake letters were spotted because they "had anomalies and had not been genuinely issued by the State Department for Defence", Kenya Standard reports.

He says he's liaising with the armed forces to find out where the letters came from, but he suspects "that parents and brokers who masquerade as senior military and police officials were involved in one way or another".

The offer of a job is the driving factor in a country where one-in-six young people are unemployed.

The incident comes at the end of the Kenyan army's month-long annual recruitment scheme for men and women aged between 18 and 26 years.

Potential recruits were warned at the time that any attempt to use fake call-up letters, bribery and other acts of corruption to gain admission to the armed forces would be treated as fraud and prosecuted accordingly, Nairobi's Capital FM reported in September.