BERLIN (AP) -- Authorities raided 15 properties across Germany on Wednesday and seized assets in an investigation into the financing of protests by the Last Generation climate activist group, prosecutors said.

Munich prosecutors said they were investigating seven people, ranging in age from 22 to 38, on suspicion of forming or supporting a criminal organization. They launched the inquiry following numerous criminal complaints they received since mid-2022.

Members of Last Generation have repeatedly blocked roads across Germany in an effort to pressure the government to take more drastic action against climate change.

In recent weeks, they have brought the traffic to a halt on an almost daily basis in Berlin, gluing themselves to busy intersections and highways. Over the past year, they have also targeted various art works and exhibits.

Their tactics have drawn sharp criticism. On Monday, Chancellor Olaf Scholz said he thought it was "completely nutty to somehow stick yourself to a painting or on the street."

Prosecutors said the people under investigation are accused of organizing and promoting a campaign to "finance further criminal offenses" by the group and collecting at least 1.4 million euros ($1.5 million). Two of them also are suspected of trying to sabotage an oil pipeline that connects the Bavarian city of Ingolstadt with the Italian port of Trieste.

Wednesday's searches -- accompanied by orders to seize two bank accounts and other assets -- aimed to secure evidence on the membership structure of Last Generation and on its financing. There were no arrests.

Last Generation has acknowledged that its protests are provocative, but it argues that by stirring friction it can encourage debate within society about climate change.