A renowned black writer has told journalism students how his career developed from writing a column as made-up agony aunt "Sheila La Roux" to sharing a cell with Nelson Mandela.

Journalist Lionel Morrison, a member of honour of the National Union of Journalists and its first black president, gave some journalistic advice, and told how his first job was clinched in 1955, bizarrely, through his knowledge of psychology and whisky.

He told them: "I was the paper's first agony aunt – luckily my mother told me what to write! With her advice, the column became extremely popular."

An idealistic reporter, he was charged one year later with high treason along with 155 other anti-apartheid activists, including Nelson Mandela and Walter Sisulu.

"There were 90 of us in a 15 by 45 foot room," he said. "I was able to overcome the fear and the darkness, but the stinking blankets were the worst."

Post-graduate journalism course leader Mark Benattar said: "It was a real honour to have someone who has contributed so much to the field of journalism and human rights in general, to come to talk to us here in Camborne."

Lionel has recently written a new book A Century of Black Journalism in Britain.