Vandals have targeted the republican plot in Milltown Cemetery in a graffiti attack.
Spray paint was used to deface an engraved copy of the Proclamation and other stone work at the heart of the memorial in the west Belfast graveyard.
Sinn Féin MP Paul Maskey described it as a "sectarian attack".
"All graveyards are sacred places and should be respected," he said.
"This attack is outrageous and does nothing other than cause distress to families whose loved ones are buried in the plot.
"I would like to commend the National Graves Association who tend to the republican plot and whose members are already involved in a clean-up of the graves."
Vandals sprayed "F**k the IRA" and "Ulster forever", and also damaged headstones in the attack.
Mr Maskey urged people with information to go to the police.