PARIS–France said on Friday it had frozen the assets of three people nine companies suspected of involvement in the development of chemical weapons in Syria.

In a joint statement, Finance Minister Bruno Le Maire and Foreign Minister Jean-Yves Le Drian said the move was aimed at cracking down on networks suspected of helping Syria’s Scientific Studies and Research Center.

The U.S. government and other countries accuse the centre of helping to develop chemical weapons for the government of Syrian President Bashar al-Assad.

“Three people and nine companies have been targeted for their role in the research and/or acquisition of materials for the development of chemicals and ballistic weapons for this country,” the statement said.

The statement did not reveal the identities of the individuals or companies.