Auckland Council has apologised for damaging the burial sites of around 170 babies in south Auckland.
Maintenance workers mowing the lawns left flowers and ornaments strewn across the ground at the Manukau Memorial Gardens.
The Downer Group contractors didn't report the damage, but distraught family members alerted them.
Chief executive Steve Killen has since apologised on behalf of the company, saying he was "personally troubled by the disrespect this shows".
He said they'll provide fresh flowers in the area and donate $10,000 to Starship Children's Hospital as an apology.
"This was a one-off, careless act and by no means represents the responsibility our 5000 employees accept every day in providing essential front line services to our local communities," he said.
"We do take full responsibility and will work with all our teams to ensure this does not happen again."
Auckland Council said it would have been a "distressing sight" for family members to find.
"We're really disappointed that this even happened, but it should have been the contractor that let us know that this had happened, then we could have gotten out there and tidied it up," spokesperson Catherine Moore said.
Auckland Council says an investigation is underway, and any affected families are being urged to come forward.