There was trouble last week in Tallaght and the second leg of Shamrock Rovers v Linfield tonight has also seen fans and police clash.
In the first leg of their Setanta Sports Cup match in Tallaght last week there were reports of unsavoury chanting and it ended with Linfield fans clashing with Gardai over the raising of some flags.
The return leg tonight in Windsor Park has also been fractious, to say the least. Reports from those in the ground suggest that both sets of fans were singing sectarian songs and the PSNI had to step in to prevent an altercation between the visiting Shamrock Rovers fans and the small attendance of home fans.
These pictures, below and above, via INPHO/Presseye/Brian Little show what happened when the Shamrock Rovers fans went through a cordon.
There are also reports of seats been thrown on the pitch, while a flare also stopped play briefly.
As for the score, Rovers won 3-1, and progressed to the semi-finals 7-2 on aggregate.
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