Bloody Sunday remembered at commemoration parade
Relatives of some of those killed on Bloody Sunday have led the annual commemoration parade in Londonderry.
It comes as the PSNI begin to interview potential witnesses in their investigation into what happened.
Thirteen people were shot dead by the Army on 30 January 1972 at a civil rights march. A 14th man died later.
In 2010, the Saville Inquiry was heavily critical of the Army, finding that soldiers fired the first shot without issuing a warning.
The report also found that all of those who were killed were unarmed. Some of them were clearly fleeing or going to the assistance of others who were dying,
As part of a fresh police investigation launched in 2012, detectives want to re-interview former soldiers and civilians who gave evidence to the Saville Inquiry or who may have information about the day.
While some relatives of those killed have indicated they do not wish to see prosecutions brought, among those in favour of such a move is Kate Nash, whose 19-year-old brother William was shot dead on Bloody Sunday.
She said she felt the police's investigation was not proceeding quickly enough.
"I can't say I'm happy with it because they were supposed to start that two years ago," she said.
"We would have expected to be much further on in this investigation than it is."
A series of notices will be placed in local newspapers and other publications to encourage witnesses to come forward again.