THE Northern Ireland Secretary, Sir Patrick Mayhew, said the Derry shooting was a "sickening attack" which would further delay Sinn Fein's acceptance as a constitutional party and entry into talks.
"She was guarding the Courts of Justice. Justice means nothing to the IRA and others like them" he added.
The Shadow Northern Ireland Secretary, Dr Mo Mowlam, described the attack as "particularly vicious".
The Liberal Democrat Northern Ireland spokesman, Lord Holme, said: "I don't know how Sinn Fein can face the electorate while the terrorists indulge in a campaign of murder and fear.
"It is important that the security forces go on to a very high level of alert to deny the terrorists the satisfaction of spreading fear and securing the publicity they crave," he added.
Just hours before the shooting the British Home Secretary, Mr Michael Howard dismissed renewed speculation of another IRA ceasefire.
He said: "If they think they can carry out those acts one day, turn around and announce a ceasefire the next day and expect everyone to forget the acts for which they are responsible, I am afraid they are seriously mistaken.