In short:

Naomi Brooks said her son and his friend walked two kilometres after they escaped from their childcare centre in Canberra last week.

Ms Brooks said she had been struggling to get answers from the childcare's provider, Northside Community Services.

What's next?

Northside said it would continue to engage with the families of the two children involved, the childcare regulator, and ACT Policing.

The mother of a child who escaped from a Canberra childcare centre says her son walked two kilometres and crossed four streets in the time he was missing from the service.

The five-year-old boy and another child managed to run away from Majura Early Childhood Centre last Monday by turning play equipment on its side and scaling a fence.

Mother Naomi Brooks said she learned about her son's disappearance when a police officer knocked on her door.

"I just froze, because when a police officer comes to your house and asks [after] your child, you think they're dead or at least seriously hurt,"she said.

"That's when I was like, 'why wasn't he at his childcare centre?'"

The pair timed their escape during rest time, and they were later spotted by two separate members of the public who called ACT police sometime after 1pm.

The children were reunited with their parents about 2:30pm, once officers worked out where they were missing from.

It is not clear how and when the centre discovered the children were missing.

Ms Brooks said she had spent the past week putting together information she had garnered from her five-year-old, police, and passers-by who stopped the children.

"It was clear that he covered about two kilometres around Dickson and they would have kept running if they weren't stopped," she said.

The centre's provider, Northside Community Services, declined to respond to specific questions about the incident, citing an ongoing investigation.

Ms Brooks said she had been "flabbergasted" by her struggle to get answers from Northside.

"The centre made a big deal about appointing an [ex] AFP investigator, but they haven't interviewed him or me about what's happened," she said.

"It's clear that they're focused on media management and their reputation … because [as of Monday] they have not called me."

"They can't pick up a phone and say sorry? I want [CEO] Dan English to pick up the phone and say sorry."

In response to questions from the ABC, Northside reiterated its public apology to the two children and their families, originally made last week.

In an update sent to parents on Tuesday, CEO Dan English said: "I know you have questions and deserve to understand what happened and what measures we will put in place as a result of the incident."

"These investigations take time, as information must be checked and verified to ensure the findings are accurate and supported by evidence," Mr English said.

Northside confirmed it had appointed an ex-AFP investigator with child-safety expertise.

"The investigation will include speaking with the parents of the children involved to hear their accounts, concerns and questions," Mr English said.

"We have increased staffing at Majura to provide additional support and supervision during this time, and a member of Northside's Quality and Compliance team is on site to support staff and families."

Ms Brooks has applied to withdraw her son and her other child from the centre because she said she can no longer trust the service's supervision.

"That gives me complex feelings because our educators have been fabulous, but it says to me they were overworked," she said.

Northside, which merged with Woden Community Services in November last year, said it continues to engage with the families of the two children involved, the childcare regulator, and ACT Policing.

"Any time outside our care and supervision, for any child in our care, is unacceptable," the centre said in a statement to the media.