Fears that extremist religious ideals were the trigger for Melbourne's fiery new gangland war have been dismissed, despite wild claims by some underworld figures.

Just days ago three men were arrested over the second arson attack on CBD venue Bar Bambi in a week.

The arrests followed a series of firebombings, shootings and attempted kidnappings across Melbourne’s late-night hospitality scene.

For months now, nightclub owners, the general public and police have searched for a reason for the latest onslaught of violence. 

Now though, underworld sources say a shadowy new organisation known only as The Cartel have been behind the brutal campaign of ruthless extortion. 

Melburnians had hoped they'd seen the end of arson attacks with the arrest of gangland kingpin Kazem 'Kaz' Hamad in Iraq in January. 

Hamad is accused of running an illicit tobacco empire that has seen countless tobacco retail shops destroyed by fire over the past few years. 

With his main rival Sam 'The Punisher' Abdulrahim dead and buried, many had hoped for an end to the carnage that has seen innocent people caught up in the chaos.

The most notable victim of that war remains Melbourne woman Katey Tangey, who died after her bungling killers torched the wrong home in a deadly escalation of the gangland conflict.

On Monday, Melbourne underworld crime reporter Ryan Naumenko claimed the new gang is behind the latest attacks on the city's struggling nightlife. 

'Outlaw Media can exclusively reveal that a group known only as "The Cartel" are behind the coordinated arson blitz targeting Melbourne’s nightclubs,' he posted to his independent news site. 

'Sources with direct underworld connections have confirmed the shadowy outfit is staking its claim in the city’s lucrative nightlife scene, running a brutal protection racket that demands venues fall into line, or burn.'

Naumenko had been closely monitoring the warring factions behind Melbourne's 'Tobacco Wars'. 

The independent reporter claimed the new crew was behind more than a dozen attacks on Melbourne hospitality businesses over the past two months. 

They include attacks on Bar Bambi, Albion Hotel, Emerson Nightclub and numerous strip clubs. 

'No one has been injured in any of the blazes, but the message is crystal clear and delivered with professional precision,' Naumenko reported.

'Club owners who thought they could ride it out are now staring down a new player that operates with zero mercy and total anonymity.

'The Cartel has landed in Melbourne, and it seems the chaos is only just beginning.'

Melbourne club owners have been confused about why their venues had been attacked. 

For a while, underworld sources had suggested the attacks might be linked to Middle Eastern gangs attempting to enforce Sharia law - the Quran's fundamental Islamic ethical code  - on 'sinful' Australians. 

Youngsters being tasked by the crimelords are said to have been lured in under the false premise of doing God's work. 

'Because they're Islamists who don't agree with Western 'debauchery' ... at least that's the line they sell to their minions,' one of Naumenko's contacts has suggested. 

A Victoria Police spokesman told Daily Mail it had become aware of chatter about the attacks being religiously motivated. 

'At this stage a motive hasn’t been established for the attacks. I appreciate there is a lot of media speculation [about religious motivation] but we are keeping an open mind and open to all possibilities,' they said.

Underworld sources have told The Age no gang or group has claimed responsibility or made any demands in order to stop the violence. 

'No one can work out why it’s happening or what they want. It just keeps happening. People are in hiding,' one source said.

The owner of another late-night bar in the CBD, who asked not to be identified over fears for his venue, told the newspaper Melbourne’s hospitality scene was in disarray. 

'It’s become a war zone out there ... every day we wake up to another fire. This is our livelihood and it’s being taken away. And the worst part is that the police and the industry don’t really know why [it is happening],' he said. 

On Tuesday afternoon, State Anti-Gangs Division Detective Superintendent Jason Kelly said police were still identifying the motice for the attacks, despite making 12 arrests already.

He told reporters police had established 'Operation Eclipse' - a major coordinated police effort by Victoria Police’s State Anti-Gangs Division. 

The operation will target organised crime syndicates believed to be behind a rapid series of 15 incidents. 

'We have a very open mind as to what is behind this. We are yet to determine the motive, and everything is currently on the table,' he told reporters. 

'It’s one of the reasons I’m standing up before you … we’re still trying to understand what is going on here, and unlike the illicit tobacco conflict … it still requires a deep dive by us in terms of what’s the root cause of what we’re seeing here.'

Supt Kelly said everything remained on the table in terms of what was the root cause of the attacks, including speculation some kind of illicit alcohol war was now emerging.

'That’s an avenue we’re exploring. Again, we don’t rule it in, and we don’t rule it out… So at the moment, we’re open,' he said. 

But Naumenko insists nightclub owners now have a clear understanding about why their businesses have been targeted. 

He revealed: 'I've been told on incredibly good authority, "The nightclubs are going to go, one by one. Maybe two by two, we will wait and see. There’s a tax. They will pay us."'