more than 600 pupils were suspended for physical attacks against school staff last year - three times more than the previous year, new figures have revealed.
According to figures published by the Department of Education, violent incidents accounted for 646 - or almost 10% - of all 7,078 suspensions in the 2015/16 academic year.
Justin McCamphill of the teaching union NASUWT blamed budget cuts as one of the underlying reasons for the huge spike in attacks.
"The NASUWT is being inundated with teachers reporting assaults that are happening to them on a daily basis," he said.
"Any discussion of violent and disruptive behaviour in schools has to be put in the context of the budget cuts that are happening in Northern Ireland, which is a significant contributing factor."
Mr McCamphill warned that as a result of budgetary pressures, schools are losing the specialist support that allowed them to work with vulnerable young people.
"Class sizes are getting bigger and not enough resources are being put into supporting pupils with Special Educational Needs," he added.
"Many young people who should have dedicated support to help them in the classroom have seen that support withdrawn.
"Schools should be havens of peace but, in too many, discipline is breaking down."
Speaking on the BBC's Stephen Nolan Show yesterday, Mr McCamphill claimed the true number of attacks could be more than 1,000 as the figures for special schools aren't included, and urged teachers to report pupils to the police.
"There does appear to be a reluctance to report assaults," he said. "Report it to police so we can log that it's happening."
Mr McCamphill also attributed the rise in staff sick days to the attacks which have resulted in increased costs for substitution cover.
"We are dealing with several members who had to take time off work but I'm sure there are some that have left their jobs because of it," he said.
The statistics show that another 1,263 suspensions related to verbal abuse of staff and 1,494 were for physical attacks on other pupils. Just over 1,400 pupils were suspended more than once, with 708 suspended on three or more occasions.
A total of 272 suspensions were issued to children attending primary school - 97 to pupils aged between four and eight.
Alcohol and drugs accounted for 184 suspensions here, according to the departmental figures. Some 19 pupils were expelled during the 2015/16 academic year, a reduction of six compared to the previous year.
The most common reasons for expulsion were verbal abuse of another pupil (26%) and persistent infringement of relatively minor school rules (26%).