Greta Thunberg has gone on trial over a London climate protest outside an oil and gas conference

Climate activist Greta Thunberg is on trial for protesting outside a major oil and gas industry conference in London last year

LONDON -- Climate activist Greta Thunberg went on trial Thursday for refusing to leave a protest that blocked the entrance to a major oil and gas industry conference in London last year.

Thunberg, 21, was among more than two dozen protesters arrested on Oct. 17 after preventing access to a hotel during the Energy Intelligence Forum, attended by some of the industry’s top executives.

The Swedish environmental activist and four other protesters face a two-day trial in Westminster Magistrates’ Court on a charge of breaching a section of the Public Order Act that allows police to impose limits on public assemblies. She and four Fossil Free London protesters have pleaded not guilty.

Thunberg and other climate protesters have accused fossil fuel companies of deliberately slowing the global energy transition to renewables in order to make more profit. They also oppose the U.K. government’s recent approval of drilling for oil in the North Sea, off the coast of Scotland.

Thunberg sat in court in a black T-shirt and black pants, taking notes as a police officer testified about efforts to disperse demonstrators who had blocked several exits and entrances for hours outside the luxury InterContinental Hotel in central London.