Victoria's work safety watchdog has exposed three more chemical dump sites in Melbourne's north, notching up the three-month stockpile total to almost a dozen.
The WorkSafe-led taskforce with the Environment Protection Authority and fire services narrowed in on three Craigieburn warehouses after a fresh tip-off, a statement on Saturday said.
It appears bulk containers at the latest locations are similar to those found at eight other sites in the northern suburbs in late December.
Security guards are patrolling the three sites around the clock with air monitoring still to be established.
It comes after up to 1.5 million litres of hazardous liquids - including industrial solvents - had been stored in bulk containers and drums at eight sites in Epping and Campbellfield.
In January, WorkSafe said it would use powers under the Dangerous Goods Act to lead a task force to remove chemicals from the sites, with containers shifted in February.
Investigations are ongoing into how the chemicals came to be stored there.
© AAP 2019