A Tel Aviv synagogue has been attacked and daubed with graffiti, apparently in response to religious Jewish attempts to ban a gay pride march in Jerusalem.
Jerusalem's gay pride march has become a regular event
Ultra-orthodox Jews have opposed the march, scheduled for next week.
Windows in the synagogue were smashed and the walls were painted with the slogan: "If we can't march in Jerusalem you won't walk in Tel Aviv".
On Wednesday evening ultra-orthodox protesters clashed with police in a district of Jerusalem.
No-one was injured in the Tel Aviv attack, which took place in a central area of the city and was reported early on Thursday.
Itai Pinkas, a member of Tel Aviv's city council and a gay community leader, told Israel's Haaretz newspaper the attack was a "malicious provocation".
"The [gay] community's struggle has always promoted values of tolerance, understanding and consideration, and such violent acts have not and will not be used as a means in the just struggle for attaining full civil rights," he said.
The planned gay pride march in Jerusalem is scheduled to take place next Friday, but police are yet to issue permits for the event.
On Wednesday night protesters in the ultra-orthodox Jerusalem neighbourhood of Mea Shearim threw eggs and rocks at cars, reports said.
Three policemen were reportedly injured, and eight demonstrators were detained.
Further protests are expected in the area in the run-up to the march.