Sectarian violence has erupted again in Syria, raising fresh doubt on the ability of the new Islamist rulers to control armed factions and calm tensions.

The Israeli military carried out a warning strike against "extremists" preparing to attack members of the Druze minority in the Syrian town of Sahnaya, Israeli Prime Minister Benjamin Netanyahu said on Wednesday in a joint statement with Defence Minister Israel Katz.

Israel said it carried out a strike in Syria against "an extremist group" that attacked members of the Druze community, following through on a promise to defend the minority group as deadly sectarian violence spread near Damascus on Wednesday.