Ballymena is set to become a ghost town after councillors narrowly voted in favour of another large out-of-town retail development, campaigners have claimed.
The warning comes after a controversial £100m 'mini-village' covering 97 acres on the outskirts of the town was passed by just five votes to four.
The plans have been brought forward by the evangelical Green Pastures Church and its pastor Jeff Wright, a former Ballymena United footballer and son of Wrightbus founder William Wright.
Those behind the sprawling 'Gateway' project expect it to open within three or four years and to create more than 1,000 jobs, but opponents claim hundreds will be lost in the town centre.
The site will have a business park, training centre, social and student houses, a nursing home, church, retail premises and more.
Mr Wright said: "I'm very pleased we have got this result. We are here to take the advice given by professional planners. The council has voted and that is what democracy is all about. We will do all in our power to help the town centre because we are here for the town, not against it."
But traders were furious with the decision. Glyn Roberts, of the Northern Ireland Independent Retail Trade Association, said: "We will take stock, but rest assured we are not walking away from Ballymena town centre.
"[This is a] disgraceful decision by the council, putting hundreds of town centre jobs at risk."
He had earlier told the council planning committee: "If you want Ballymena to become a ghost town, vote in favour of this."
His comments were echoed by planning consultant Des Stephens, representing Ballymena Chamber of Commerce, who said: "It is a disappointing decision that no sane council could possibly approve something so far out of the town centre when the town centre is already on its knees.
"The impacts were not properly assessed. There were a lot of flaws and this could well be the subject of legal challenge."
Planners had rejected a plan for the business element of an urban village. But this week, it was revealed a revised proposal complied with the rules, which also gave councillors the final say.
North Antrim DUP MP Ian Paisley, who earlier addressed the committee in support of the scheme, admitted he was guilty of a U-turn. "When the first application came in, because of the scale, I was opposed to it," he said. "After getting a rejection, the (developers) listened to advice and reduced the size and scale of the application. We now have an application which I do not believe will damage the locality."
But his colleague, North Antrim DUP MLA Paul Frew, said the impact on the town centre would last "for at least 300 years".
Not all councillors sit on the planning committee, but two of those who do - DUP councillors Audrey Wales and Beth Adger - declared an interest and did not take part in the vote.
Principal planner Gary McGuinness said there were 44 letters of objection, mainly about the impact on the town. But he added that planners had recommended approval of a 4,100sq m food store, "the size of a standard Asda" and smaller than the original 6,000sq m application.
He also said the projected turnover at the smaller store was deemed to be acceptable as to the impact on the town centre.
Mr Wright earlier told the committee the new mini-village would "make a difference in the life of the poorest and most broken people in our town".
Robert Logan, chair of the council planning committee added: "The committee understands that not everyone will be in favour, however this decision was based on the evidence that was presented to the committee. Mid and East Antrim Borough Council will listen to all concerns raised. Following the transfer of planning powers to councils, every planning decision is made on a professional basis, in line with policy."