“This Leonardo DiCaprio is a cool guy, right? Giving money to torch the Amazon,” Mr. Bolsonaro said without presenting evidence in front of the presidential residence.

A representative for Mr. DiCaprio did not immediately respond to a request for comment.

Mr. DiCaprio has been an outspoken advocate of measures to combat climate change, posting frequently on Twitter about environmental issues, including the Amazon forest fires. His foundation, which is focused on projects that “protect vulnerable wildlife from extinction,” is part of the Earth Alliance.

Mr. Bolsonaro’s remarks came after four members of the nongovernmental organization Alter do Chão Fire Brigade were arrested on Tuesday and accused by the police of setting fires in order to document them and drum up more donations.

They were released on Thursday on a judge’s order.

Politicians and nongovernmental organizations had fiercely criticized the arrests, saying they were part of a concerted attempt by Mr. Bolsonaro’s government to harass environmental groups.

Mr. Bolsonaro has repeatedly lashed out at various factions over the forest fires and the international concern they have attracted.