By Joseph Akwiri
MOMBASA, Kenya, Jan 22 (Reuters) - A trial of four Kenyan policemen accused of killing the son of a British aristocrat began in a Mombasa court on Tuesday, with prosecutors saying they plan to bring 45 witnesses to testify.
Naftali Chege, Charles Wangombe Munyiri, Baraka Bulima and John Pamba are charged with the killing in May 2012 of 28-year-old Alexander Monson.
Monson was found dead in his jail cell after being arrested for what the police said was smoking cannabis during a night out in Diani, near Mombasa on Kenya's Indian Ocean coast.
Hilary Monson, Alexander's mother, told the court in Mombasa that her son was not a drug addict at the time of his death, contradicting claims by police that he died of a drug overdose.
"I know my son, like many youths, used drugs. He had a problem at one point but he had gone through a great deal of suffering to sort himself out," she said.
Alexander Monson's family and local rights groups demanded an inquest into his death which found there had been attempts to cover up what had happened and threats against witnesses.
Two reports by government pathologists, seen by Reuters, concluded that he had died after suffering a traumatic blow to the head.
"We are very concerned that it has taken already a very long period and they say that justice delayed is justice denied," said Hussein Khalid, director of local rights group Haki Africa.
At their first appearance in court in July, the accused denied the charges.
Presiding judge Erick Ogola said he would give the case top priority, adding: "I will expect all parties involved to be cooperative." (Additional reporting by Hereward Holland in Nairobi Editing by George Obulutsa and Gareth Jones)
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