"These were just people who were very much of their community, " said Karen Leathem, a historian with the Louisiana State Museum.

CNN: A modern celebration of African-American history

The ceremony featured speeches from Warrington Mayor Steve Wright, Warrington Council leader Terry O'Neill, minister of state for Northern Ireland Mike Penning MP and Mayor of Lisburn Alderman William Leathem.

BBC: Warrington recalls IRA bombing 20 years on