The incident at Lilian Bland Park cenotaph has been condemned as sectarian and disrespectful.
Police said they received a report of criminal damage which occurred at the war memorial sometime between 1.45pm and 2.00pm.
Inspector Patton said: “Enquiries are ongoing in relation to this incident, which is being treated as a sectarian hate crime.”
Thousands expected to take part in 'Derry Day' this weekend
Two new arrivals in DUP camp as UUP councillor Alan Lewis defects alongside serial party-switcher Henry Reilly
Crawfordsburn Country Park: Five PSNI officers injured bringing crowd of 600 under control - two teens arrested - parents asked to know where their children are
Search for missing man ends with body found on north coast
Esmond Birnie: The protocol is not as claimed boosting growth in Northern Ireland
Glengormley Councillor Julian McGrath has appealed to those behind attacks to stop. The Alliance representative said the incident, which took place in broad daylight, saw poppy wreaths destroyed.
“This latest attack is yet another disgusting act of sectarian vandalism and disrespect,” he said.
“These actions are aimed purely at raising tensions in the town and I appeal directly to those behind them to stop. All sections of our community here abhor such behaviour.
“The memorial in Glengormley represents those who fought and died to enable us to enjoy the freedoms we enjoy today. This despicable vandalism is particularly low and achieves nothing.
“I urge anyone with information on this attack or previous ones to contact the police with it immediately.”
There was similar vandalism at the Ballyclare Road location in March after which the then Mayor of Antrim and Newtownabbey, Councillor Jim Montgomery, relaid a wreath. He did the same following a repeat attack in April when scorch damage was also caused to the memorial. Click here
Inspector Patton added: “We would appeal to anyone who witnessed the incident or who has any information, to contact police on 101 quoting reference number 1032 08/07/21.”
A report can also be made using the online reporting form via www.psni.police.uk/makeareport
Alternatively, information can be provided to Crimestoppers anonymously on 0800 555 111 or online at www.crimestoppers-uk.org
Thank you for reading this article. We’re more reliant on your support than ever as the shift in consumer habits brought about by coronavirus impacts our advertisers. Please consider purchasing a copy of the paper. You can also support trusted, fact-checked journalism by taking out a digital subscription of the News Letter.