Israel's military says a rocket fired from neighboring Sinai, where Egyptian troops are battling Islamic State militants, has struck southern Israel. There was no damage and no one was hurt.

The military says the rocket hit open field in southern Israel Friday afternoon. Sirens were heard in parts of southern Israel, warning of incoming fire.

Sinai borders both Israel and the Gaza Strip. The fighting there started on Tuesday, when militants unleashed a coordinated wave of attacks on Egyptian troops. The escalation is worrying Israel.

Israel has said the Islamic militant group Hamas, which rules Gaza, is helping Islamic State-linked militants in Sinai.

Earlier Friday, the military closed a road in the south as a precaution against Sinai fighting spilling over into its territory.