A number of parents joined the picket at the school

The five unions involved said they would now ballot members for an all-out strike of thousands of assistants across Northern Ireland.

They said a letter from management they received ahead of talks did not answer any of their complaints properly.

Meanwhile, a special school in Dundonald closed on Friday because of a one-day strike by classroom assistants.

The trade union, Nipsa, said about 40 assistants at Tor Bank special school were frustrated at delays in bringing in new pay agreements.

Picket line

The school has 130 pupils with severe learning difficulties on its roll-book.

A number of parents turned up at the picket line on Friday to support the classroom assistants' action.

The main problem in the wider dispute centres on the number of hours the staff work compared to other non-teaching staff.

The management side said they were committed to giving equal treatment to all non-teaching workers whose jobs are being re-evaluated.

They said no classroom assistant would lose money from the regrading exercise and many will gain extra pay.

The regrading was first announced 10 years ago and any extra salary will be back paid to 1995.

Nipsa has urged the education boards to give "proper recognition" to the contribution made by classroom assistants.

'Last resort'

Nipsa general secretary John Corey said strike action was a last resort.

"The frustration of our members has boiled over at the attempts by the education and library boards to thwart progress on the job evaluation of classroom assistants' jobs," he said.

"Classroom assistants are not prepared to wait forever to have their job evaluation process completed so that members can be paid a proper rate for this work."

Alliance Party election candidate Kieran McCarthy, who joined the Tor Bank picket line, said the assistants felt this was the only course of action, having waited for 10 years for evaluation.

"The sooner the department acts, the quicker this can be resolved and the assistants can get back to looking after special needs children," he said.