"It looks to us like the crosses, which are all quite old and not in the best condition, have been moved perhaps in an effort to 'tidy' them away.
"We also believe that these crosses were previously lying on plots or quite deteriorated by the passing of time," he said.
Mr Webb said some of the discarded crosses had identifiable names or plaques attached and the council would look at records and replace them.
"There are, however, a small number of crosses with no name -- we'll store these and work with any families that come forward to identify and return their crosses," he said.
Cemetery staff would attempt to get in touch with families and offer a new replacement cross to those who wanted them.
"We have carried out an initial search of our database and have family details for the eight crosses that had name plaques so we will attempt to make contact over the next day or so," he said.
Mr Webb said if people were concerned their loved one's grave might be affected by the crosses vandalism, they should approach council for help.
Inquiries could be made to Waikumete Cemetery on 09 818 5615.