A section of Derry's walls collapsed yesterday, temporarily halting site clearance on the city's adjoining £13 million Millennium Theatre Complex project.
A 10-metre section of the East Wall caved in on Monday night, leaving a gaping hole. The walls were built between 1614 and 1619. They were never breached during sieges of 1641, 1649 and the Great Siege of 1689 - which is why Derry is also called the Maiden City.
The collapse prompted an emergency meeting last night between the Department of the Environment, representatives of the developers, Fermac Properties, and members of the Derry Theatre Trust.
The trust's chairwoman, Cllr Annie Courtney, said the collapse was a serious incident. "It's one of those things that can happen at a construction site anywhere. There are bound to be incidents that you can't always allow for, but we are deeply concerned that something so important to the people of Derry has been breached.
"We now have to see what can be done to remedy the problem. The main thing is that no one was hurt, but I'm disappointed that it has happened. We now have to find out how it happened and why it happened," she said.
Meanwhile, Mr Miceal Canavan, who is leading a campaign against the East Wall complex development, said all site work should be halted. "The operations should be suspended and there should be an alternative site for the development. Both unionists and nationalists are concerned about the damage to the walls. Over the last 30 years a lot of damage was done to the city's buildings, but I don't ever remember the walls being attacked. Now they're under attack.
"The entire foundations of the walls will now have to be examined by the developers and it would be madness to continue with this project," he said.
Mr Niall O'Kane, spokesman for the developers, said they noticed on Monday there had been a small movement on the section of the walls which later collapsed. "We were in the process of taking steps against any slippage of the walls when a 10-metre section fell into the site. We have taken quite a few steps to ensure the stability of the walls and we have worked with the DOE [Department of the Environment] over the last six months to a year to ensure that the design of the building doesn't impact on the stability of the walls.
"From our initial investigation the slippage was caused by poor foundations to the inner skin of the walls. It appears this section which has slipped was built on fill material and not on clay and when we were excavating back from the walls this material became loose and caused the slippage," he said.