More than 100 climate activists will protest tonight as part of a planned rally during after-work peak hour.

After an initial rally at the State Library from 5pm, the protesters are expected to branch off into groups to stage smaller demonstrations at undisclosed locations across the city to obstruct foot and road traffic.

The UK-based activist organisation behind the protests, Extinction Rebellion – also behind another large protest in May – is demanding governments declare a climate and ecological emergency and reduce greenhouse gas emissions to net zero by 2025.

Yarra Trams expects disruptions to Swantson Street services from 5pm to 7pm, and advises commuters to plan their journeys accordingly and allow time for delays. Victoria Police is aware of the planned protests.

“Police make every effort to engage with event organisers to facilitate their right to lawful protest whilst discussing expectations around appropriate behaviour. As always, anyone coming to an event in Melbourne looking to disrupt others or create conflict and incite violence can expect a firm response from police,” says a post on the Victoria Police Facebook page.

While concerns have been expressed that the demonstration will affect tonight’s football final between Collingwood and Geelong at the MCG, the rally is scheduled to finish at 7pm, an hour before the first siren. As reported by the Age the finish time for the protest is deliberate; some protestors hope to attend the game.

Melburnians can expect more climate emergency demonstrations soon. There is a Princes Bridge block scheduled for Saturday September 14, and a protest against Queensland’s Adani coal mine on September 20 from 2pm to 4pm in Treasury Gardens, three days before the UN Climate Action Summit in New York City.