Talks between Nipsa and the Education and Library Boards broke down last night with thousands of classroom assistants refusing to return to work until their demands are met.
At the end of the first day of a three day strike, relationships between the unions and management appeared at an all time low and all out strike action appeared likely.
Up to 3,000 members of public service union Nipsa staged the first day of a three day walk out yesterday in a dispute over pay and terms and conditions.
Special schools across the province forced to close while pupils at mainstream schools with special needs were also forced to remain at home. The situation is expected to deteriorate as strike action continues.
If no agreement can be achieved, the classroom assistants will only return to work on Friday before beginning all out action on Monday.
Talks were held yesterday in an attempt to break the deadlock but these ended without a resolution and sources within Nipsa said the meeting had strengthened the resolve of members.
Nipsa representative Brian Booth said: "Talks broke down and it was quite acrimonious. Management just haven't moved at all and our members will not go back to work until their demands are met.
Meetings are expected to take place throughout the province today where classroom assistants will make a decision on whether to continue industrial action. It is expected that Nipsa members will reject the latest pay offer form management, which includes an extra £15m for a one off payment to classroom assistants.
However, Helen McClenaghan, chief executive of the Southern Education and Library Board, has defended the offer as fair.
Meanwhile, Frank Bunting from the Irish National Teachers' Organisation said teachers should stand behind the classroom assistants.