Arsonists have targeted two Melbourne venues in the lead-up to an underworld figure's boxing match.
Sam "The Punisher" Abdulrahim was due to fight at the Furlan Club at Thornbury in Melbourne's north on Saturday, with the venue set alight at 2am on Thursday.
A fire then broke out at the Emerald Reception Centre at Thomastown about 6am.
Both businesses were significantly damaged and flames caused millions of dollars worth of damage, Victoria Police Detective Inspector Graham Banks said.
He stressed the affected businesses were not believed to be linked to an ongoing conflict over illicit tobacco, which has so far been connected to 38 arsons in Victoria.
"These business premises are not in any way, shape, or form believed to be involved in anything illegal or anything to do specifically with the illicit tobacco market," he told reporters on Thursday.
"Police believed they were chosen specifically because they'd been hired by people who had involvement in the illicit tobacco market who have events at those premises."
An arson specialist examined the scenes on Thursday and the organised crime-focused Taskforce Lunar is investigating.
Abdulrahim is a former Mongols bikie and professional boxer.
Two allegedly stolen cars were found burnt out near the venues and Det Insp Banks said it was unclear whether one group of offenders committed both attacks.
"These people will likely be gang-related individuals or people from that sort of background who have committed the offence of arson," he said.
"They will undoubtedly, in my experience, have been directed by another party."
He said detectives were keeping "a very open mind" about who ordered the attacks and called on members of the public who saw anyone acting suspiciously at either venue to come forward.
Investigators from Taskforce Lunar separately arrested three people on Wednesday and seized more than $250,000 in cash allegedly linked to Victoria's illegal tobacco war.
Officers raided properties at Altona North in Melbourne's southwest, including a business where they seized drugs, an allegedly stolen motorcycle and a ballistics vest.
A 39-year-old man and 37-year-old woman were charged with possessing a drug of dependence.
The man was also charged with possessing a prohibited item and the duo was bailed to front Melbourne Magistrates Court on March 20.
Investigators also arrested a 48-year-old man from South Kingsville after they found him in a car with more than $250,000 in cash in its boot.
Officers alleged the man had ties to organised crime syndicates involved in the illicit tobacco trade.
He was yet to be charged as of Thursday afternoon.
Police urged anyone with information about the incidents to come forward.