MEGADETH star Dave Mustaine once incited public unrest when he played a concert in Northern Ireland, because he unwittingly expressed support for the Irish Republican Army (IRA).

The HOLY WARS frontman was so intrigued by a discussion about the problems between Northern Ireland's Catholic and Protestant communities, he dedicated a song to what had been described to him as 'the cause'.

But little did he know 'the cause' was a euphemism for the IRA, which at that time conducted terrorist attacks both in Northern Ireland and mainland Britain as it sought unification with Ireland.

Mustaine recalls, "When I was in Ireland, somebody talked to me about 'the cause', the reason why they were killing so many Catholics and Protestants.

"To me this made sense, and from the stage I dedicated a song to 'the cause'. The next day, we received threats and had to travel in a bulletproof bus.

"It turns out 'the cause' was the way in which Irish would call the IRA. I never felt so stupid."