Around 50 climate activists were detained in the Australian state of New South Wales after they hopped on a coal-laden train and began shoveling the cargo out of the wagons.

The train came to a halt near Newcastle, which is a major coal export terminal.

Rising Tide, a protest group, has called for the closure of all new coal projects.

Climate change is a contentious subject in Australia, which is the world’s largest coal exporter.

The world has already warmed by around 1.1 degrees Celsius since the beginning of the industrial age, and temperatures will continue to rise unless governments around the world drastically reduce emissions.

The group tweeted a photo of demonstrators on and around the stalled train.

“We have halted coal imports into the world’s largest coal port, demanding that the ALP [ruling Australian Labor Party] heed UN warnings and immediately cancel all new coal projects,” the tweet said.

Rising Tide stated in a statement that 20 members of the group clambered onto the train with shovels to unload the coal, while another 30 gave backup.

According to police, 47 protestors were charged with “rail corridor offences” and freed after receiving court appearance reminders.