The culprits stole 80 plaques from the Altona Memorial Park in Melbourne's west some time between Tuesday and Wednesday, police said.
The bronze plaques were erected in memory of children by their families in the Garden of Little Angels in Altona North.
Thieves stole 80 plaques from a cemetery in what has been described as a "disgusting" crime. (Morgan Hancock/AAP PHOTOS)
Detective Senior Constable John Randone said police believe the plaques were taken for financial gain.
"This is a disgraceful and really disturbing act," he told reporters.
"Our focus is to get those plaques back to the families to provide what level of comfort that we can."
He said the culprit would have "no doubt" the plaques were from the section of the cemetery dedicated to children.
"In my seven years of policing, I haven't come across something like this, particularly at a cemetery."
The Greater Metropolitan Cemeteries Trust which manages the memorial park is working with police, including handing over CCTV footage, after initial inspections indicated bronze plaques had been removed.
Detective Senior Constable John Randone said the thefts were a "really disturbing act". (Morgan Hancock/AAP PHOTOS)
The trust contacted affected families and would support them through insurance claims to get the damage repaired, chief executive Andrew Eriksen said.
"This type of act is highly distressing, in any instance, for the bereaved friends and family affected," he said in a statement.
"The fact that the memorials impacted are those of children is all the more devastating."
Hobsons Bay City Council Mayor Matt Tyler slammed the "despicable" actions, saying he cannot imagine how heartbreaking this must be for families who have already experienced such heartache.Â
"It's just the most disgusting act to steal anything from a cemetery, let alone where little children have been buried," Mr Tyler told AAP.
"It's sad, it's disgraceful, and it's heartless."
Mr Tyler said he would advocate on behalf of the community to have the plaques restored if they were not recovered.
Police are appealing for information from the public as they investigate the crime. (Morgan Hancock/AAP PHOTOS)
"(The community) is full of love, connection, respect and tolerance and this runs in exactly the other direction to that."
Police are appealing for anyone with information or video footage to come forward and have urged scrap metal buyers to report suspicious activity.
Parents of one baby buried in the Garden of Little Angels launched a petition in 2018 to have the area renamed from the "Children's Section".
"After visiting other parts of the Altona Memorial Park we quickly realised that everything had been given wonderful names... no other section was titled after the group that was buried there," the petition read.
"This is when we decided that the name needed to change, it is too impersonal and the ones that were buried there deserved a lot more."
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