The last contingent of Irish troops to serve as UN peacekeepers in the Horn of Africa has left Eritrea but investigations continue into allegations of “sexual misbehaviour” by members of the group that preceded them, the UN said today.

An investigation was ordered tonight into allegations that Irish soldiers serving in Africa hired prostitutes including a 15-year-old girl.

An Irish soldier serving with the UN peacekeeping mission in Eritrea was sent home for making a pornographic video with a local woman.

More than 1,600 troops paraded through Dublin today, with President Mary McAleese taking the salute, to mark the withdrawal of Ireland's United Nations force from Lebanon.