Its national executive member Jim Boumelha was among staff who said they reported for work last week but found their offices locked by security guards.
The five affected staff present were told redundancy notices would be sent to their homes, he said.
NUJ general secretary Jeremy Dear said: 'Haringey council has completely reneged on its responsibilities to staff and it is a disgrace that any employer should treat its staff in such a shameful way.'
Haringey chief executive David Warwick said: 'We felt the time was right to look at the unit's efficiency.'
Matters had been handled in line with personnel procedures, he said.