POLICE claim they have made another breakthrough in their war on Melbourne's graffiti menace.

A second alleged key member of the 70K graffiti gang was arrested at his Mt Eliza home on Friday night.

The 26-year-old will be charged on summons with causing criminal damage after allegedly painting extensive graffiti on trains and trams.

The Herald Sun revealed on Saturday police believed they had smashed the 70K gang, which is accused of leaving a $1 million trail of damage to trains and property across the city.

The name 70K is short for 1970s Kids and refers to the decade in which members were born.

One alleged ringleader, who uses the tag Bonez, was arrested and questioned last month and will face charges of criminal damage, which carry a maximum 10-year jail sentence for each offence.

Police have launched an international manhunt for a second alleged ring leader, who uses the tag Stan or Stanley, after he fled to Europe.

The breakthrough is believed to be the biggest arrest in Australian history relating to graffiti on public transport. In Friday's arrest, police also seized spray paint and other evidence allegedly linked to graffiti on trains.

Supt Kevin Sheridan said a man was arrested and taken in for questioning after raids on his two homes in St Kilda and Mt Eliza.