THE Birmingham pub bombings occurred fifty years ago on November 21, 1974, when bombs exploded in two public houses in central Birmingham — the Tavern in the Town and the Mulberry Bush. The explosions killed 21 people and injured at least 170 others. This week a memorial service was held in Birmingham City Centre to mark the event. Our photographer Chris Egan was there... The memorial service held in front of New Street Station in Birmingham (Pics: Chris Egan) Bishop Challoner students perform the song A Million Dreams during the memorial servicer (Pics: Chris Egan) Irish ambassador to the UK, Martin Fraser spoke at the event (Pics: Chris Egan) Irish Ambassador Martin Fraser and other dignitaries guests observe a minute's silence at the memorial event (Pics: Chris Egan) Prayers were read by the Most Reverend Bernard Longley, Archbishop of Birmingham and Right Reverend Dr Michael Volland, Bishop of Birmingham (Pics: Chris Egan) Mary Doheny nee Reilly prepares to lay roses for her brothers Desmond and Eugene, who…