Landlords are being urged to think twice about leasing shopfronts to businesses that might be targeted as part of Victoria's tobacco wars.
Police have investigated 60 arson attacks at tobacco or vape stores across the state in the past 15 months.
Police believe those firebombings are linked to conflict between crime syndicates over illegal tobacco.
Other venues, including gyms, private homes, restaurants and cars have also been targeted.
Investigators have employed "unique" measures by contacting landlords directly, warning them of "adverse impacts" to insurance coverage.
Acting Commander Jason Kelly said he hoped the letters would prompt discussions between landlords and their insurance companies.
Two letters will be distributed by councils across Victoria in the next fortnight - one for landlords of shopfronts that have been previously targeted and another for landlords at risk of being targeted.
The letters will highlight the risks around businesses that are engaged in illicit activity, and the risk they present.
"It is a time for landlords to reflect on whether they are prepared to carry that risk, knowing they may be uninsured or an insurance claim may be rejected," Cmdr Kelly told reporters on Monday.
""It's a very public conflict we are seeing."
He hoped this information would prompt landlords to think twice before entering a lease arrangement or renewing a lease arrangement with a tobacco or vape store.
Plans by the state government to introduce legislation to establish a tobacco retailer and wholesale licensing scheme have been welcomed by Victoria Police.
That legislation is expected to be introduced in the second half of 2024.