Israeli police are investigating hate graffiti that was sprawled on the walls of a reform synagogue in the city of Raanana and death threats addressed to some reform leaders.

Spokesman Micky Rosenfeld says a knife was also found at the Raanana synagogue on Thursday.

Photographs in the Haaretz newspaper show envelopes with names of some of the leaders, including the president of America's Union for Reform Judaism, Rabbi Rick Jacobs and also Anat Hoffman, the chair of Women of the Wall.

The group is pushing for equal rights for non-orthodox streams of Judaism at the holiest site where Jews can pray. It's run under strict ultra-Orthodox Jewish norms, including separate male-female prayers.

In January Israel said it would recognize a mixed-gender area at the Western Wall, but the plan stalled.