A Colombian trade union leader was shot dead in northern Colombia on Monday, the third such killing in a week.

Jairo Cruz was gunned down on his way to work in an agricultural concern near San Alberto, where he was trade union organiser.

Last week saw the deaths of a health union official and of the vicepresident of one of Colombia's main trade union organizations.

The killings have occurred during a three week-old strike by Colombia's public sector workers.