The family of slain journalist Steven Sotloff is suing Syria in U.S. court, claiming the government of President Bashar Assad provided support to Islamic State militants who carried out the gruesome beheading.

The lawsuit filed Monday in federal court in Washington seeks tens of millions in damages from Syria for Sotloff's 2014 killing. It's far from certain Sotloff's South Florida-based family would be able to collect money if they win the case.

Sotloff was kidnapped in August 2013 after crossing into Syria from Turkey, according to the lawsuit. He was killed on Sept. 2, 2014, and a video was distributed documenting his death.

The lawsuit contends Syria is liable because it provided financial, material and military support to the Islamic State. Syria has not yet answered the lawsuit.