A number of vigils are being held across Northern Ireland for murdered journalist Lyra McKee.

The 29-year-old was shot dead in the Creggan area of Derry on Thursday night.

Two men, aged 18 and 19, have been arrested under anti-terrorism legislation in connection with her death.

Around 200 people attended a vigil in Omagh organised by the NUJ and Omagh Trade Unions Council.

One of the organisers, Anton McCabe from the NUJ National Executive, described Ms McKee as a personal friend who celebrated life and  its diversity and stood for all the principles that the gunman in the dark would like to deprive us of.

One of those principles was the right to marry her partner and the love of her life, Sara - a right not recognized legally in Northern Ireland.

He said her main ambition in journalism was to improve the lives of others.

Several prominent local people attended the vigil, including Michael Gallagher, whose son Aidan was killed in the Omagh bomb 21 years ago.

Further vigils are taking place in Enniskillen, Dungannon and Newry at 3pm.

A minute of silence was observed at an event at Belfast City Hall in support of the Good Friday Agreement.

This morning the Chairman of the 1916 Relatives Association Brían O'Neill described the killing as "an absolutely atrocious act" and offered condolences to Ms McKee's family and friends. 

He was speaking at an annual commemoration event at the Garden of Remembrance in Dublin.

He said the true heirs to the men and women of 1916 are the Irish Defence Forces, and he hopes those responsible are brought to justice and will reflect that the vast majority of people in the country do not support their actions.

Mr O'Neill said while it is unfortunate that there is not a united Ireland and part of the country is still in the United Kingdom there is a peace process which has brought huge dividends to people north and south over the last 21 years.

He added that it is unfortunate that there is a small element determined to destroy all of that.

Additional reporting Vincent Kearney