A system breakdown was responsible for the problems with KPN phone networks on Monday and three back-up systems for the 112 emergency number all failed to work, justice minister Ferd Grapperhaus told MPs on Tuesday afternoon.

The initial analyses show that something went wrong in the back-ups,’ Grapperhaus said. KPN is now trying to establish what happened and, the minister said, the results of that investigation will be double checked.

The breakdown meant that the 112 emergency phone line was out of action for several hours and the emergency services resorted to using other numbers.

MPs called on the minister to overhaul the emergency number system but Grapperhaus declined to comment on alternative plans, pending the outcome of the review.