Man with mental age of less than 10 was arrested by Army in field in 1974 . British government later intervened and investigation re - commenced this year . A former British policeman has now been arrested over the years . The suspect has been sent to lo Ireland for questioning .
Man with mental age of less than 10 was shot by Army in field in 1974 . British government later apologised and investigation re-opened this year . A former British soldier has now been arrested over the death . The suspect has been taken to Northern Ireland for questioning .