An Israel-based rights organization says it has filed a war crimes complaint against the top leader of Hamas for executing Palestinians without trial during the Gaza war this summer.

The Shurat HaDin Law Center filed the complaint Wednesday at the International Criminal Court in The Hague, The Netherlands, against Khaled Mashaal, who leads Gaza's ruling Hamas group from exile.

According to the complaint, Mashaal "had knowledge of the executions, oversees Hamas' governance of Gaza, and actively encourages and supports the executions."

Dozens of Palestinians were executed by gunmen during the fighting with Israel this summer. The Palestinian Center for Human Rights at the time urged an immediate halt to the killings which it called "extrajudicial executions."

Hamas declined to comment.