Two training camps used by Hamas, the Islamist group that rules the blockaded enclave, were hit in Thursday's attack, with no casualties reported, witnesses said.

Israeli war planes struck a security post and part of an underground site used to produce rocket engines, the country's military said in a statement.

Earlier, a rocket fired from Gaza struck southern Israel, causing slight damage to a house but no injuries, police said.

No faction claimed responsibility for what is the second such attack in days.

An upsurge of violence in Israel and the occupied Palestinian territories has raised fears of a slide back to wider conflict.

Since March, Israeli forces have killed at least 29 Palestinians in West Bank raids, while a series of deadly Arab street attacks have killed 14 people in Israel.

In a statement, Hamas said Israel's bombing will only encourage Palestinians to "resist the occupation and step up their support for Jerusalem and its people".

Confrontations in Jerusalem's Old City - particularly at Al-Aqsa mosque compound, known to Jews as Temple Mount - pose the risk of a relapse into a broader conflagration like last year's 11-day Israel-Gaza war, in which more than 250 Palestinians in Gaza and 13 people in Israel were killed.

Tensions this year have been heightened in part by the Muslim holy month of Ramadan coinciding with the Jewish celebration of Passover, which sees a rise in the number of Jewish visitors to the compound, revered by Jews as the site of two ancient temples.

Palestinians see such visits as a provocation, at the third holiest site in Islam.

Australian Associated Press