The sisters of Robert McCartney have accused Sinn Fein of "creating a wall of silence" to protect the killers of the murdered man.

Returning from their trip to Washington, Catherine McCartney said the continuing cover-up must be broken "but we need help, constructive help, not just words".

The family said they had succeeded in rallying American support for their campaign to see the IRA members who murdered their brother brought to trial.

But McCartney added: "It's no good just sitting on the sidelines calmly giving support, we need action not just from Sinn Fein, who created the wall of silence, but also from the Irish and British governments to make sure that they do something so that the wall of silence is broken down."