Staff at a Rotorua early childhood centre "should have called for back up" before three children escaped on trikes and got 320m down the road, according to newly released Ministry of Education documents.

On Tuesday, March 6, the 4-year-old girls fled ABC Sunset Rotorua for two to five minutes after one climbed on top of a trike and unlocked a 1.7m gate.

According to documents released to the Rotorua Daily Post under the Official Information Act, the children escaped while a reliever was distracted by another child who had an "outburst" and hit a teacher with a piece of wood from the carpentry area.

The trio rode up Sunset Rd and crossed the Kusabs Rd intersection.

Staff were alerted by a member of the public, and the children were caught outside 5 Edmund Rd, despite pedalling faster "to get away from the adults".

Parents were alerted by phone and met with management the next morning.

ABC Sunset Rotorua is licensed for 65 children, including 15 under-2-year-olds.

In a non-compliance report, a centre manager said: "The head teachers are aware that they should've called for back up support as there were five staff indoors".

At the end of March, the centre applied to the Wright Family Foundation to fund a teacher aide.

The application described "high levels and feelings of stress due to the budgeted number of teachers" and that "unavailability of an extra support person" was compromising staff and child safety.

"Permanent staff member has been punched in the face within the last month... Staff regularly spat on and children receiving injuries from other children. Six parent concerns regarding their children's safety and their children being too 'scared' to attend the centre due to the aggression of [name blanked out]."

The application also listed types of difficult behaviour from some children, including extreme levels of anger, destroying resources, swearing, spitting and biting, throwing objects and hiding from teachers.

The application stated: "We have made multiple referrals to Special Education to access support for our children's complex needs but find this to be an extremely long wait."

It said the centre worked with a "high percentage of vulnerable families" and a small number were in emergency housing.

"Around 8 per cent of our children are in custody of extended family or Oranga Tamariki associates."

Fiona Hughes, the deputy chief executive of the ABC centres' overseer BestStart Educare, told the Rotorua Daily Post parents had been "very considerate and understanding" after the March 6 incident.

The Official Information Act documents listed follow-up changes made by the centre, including locking and fencing off the gate opened, allocating a different fire exit, professional learning and development for supervisors, teaching road safety in the curriculum and reviewing the supervision roster.

This week Hughes said that since March, two of the girls on trikes had started school, one remained at the centre, and the child that hit the reliever was no longer there.

She said staff were commended when the ministry visited on "how promptly and efficiently they had acted".

The full licence for the centre was restored on April 9.

Hughes said the teacher aide started on March 28 and worked 30 hours a week.

"We made an application [for teacher aide funding] to the Wright Family Foundation after we had pursued all other avenues available to us."

She said the centre was not understaffed on March 6 and there were 10 teachers working that day. The Government's minimum ratio is eight.

Hughes also said the centre was "very well known with a great reputation" in the community.

Upon releasing the documents, Ministry of Education deputy secretary for sector enablement and support, Katrina Casey, said the ministry was confident the centre took the incident "very seriously" and had "all the necessary measures in place to mitigate the risk".

The documents said the centre's January 2018 Education Review Office report showed the service was "well placed".

Rotorua Lakes Council checked the centre's building's warrant of fitness and ministry staff visited on March 8 and reviewed all procedures.

The ministry issued a provisional licence and representatives visited at least once a week for a month, and then fortnightly, until they were satisfied licence breaches were remedied.