The union boss who allegedly threatened to “put an axe” in the head of the late Labor MP Jane Garrett is vowing to bring down Premier Daniel Andrews on election day, with supporters to target Labor’s most vulnerable seats.

The secretary of the United Firefighters Union Victorian branch, Peter Marshall, who has previously categorically denied accusations of bullying Ms Garrett, is going to war with the premier over the state government’s failure to meet pay and other demands, using a $1 million war chest.