It comes after an Israeli operation against militants in the West Bank left nine Palestinians dead.
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Israel has carried out air strikes on Gaza in response to rocket fire as tensions soar in the wake of a deadly army raid in the occupied West Bank.
Six rockets were fired, reports from Israel say, with Israel attacking what it said were militant sites.
There were no reports of injuries on either side.
Militants warned of a response after nine Palestinians were killed in the Jenin raid, which Israel said was to thwart “imminent terrorist attacks”.
Two rockets were fired around midnight (22:00 GMT Thursday) but were intercepted by Israel’s anti-rocket Iron Dome system, the Israel Defense Forces (IDF) said. Air strikes swiftly followed, targeting what the IDF said was an “underground rocket manufacturing site” in the central Gaza Strip belonging to the Islamist militant group Hamas, which governs the territory.
A second salvo of rockets was fired hours later, landing in open ground, shot down or falling back down in Gaza, the military said. Israel subsequently hit a site which it said was “a significant centre of Hamas terrorist activities” in the northern Gaza Strip.
No group admitted to firing the rockets, though Israel holds Hamas responsible for all attacks from Gaza.
The overnight exchange followed the deadliest incident of its kind in years after Israeli forces entered the West Bank city of Jenin to arrest an Islamic Jihad “terror squad”. The IDF said it was acting on accurate intelligence about plans by the cell to attack Israelis.
Forces surrounded a building in the city’s urban refugee camp where an intense gun battle erupted. Israel said three armed suspects were “neutralised” after they opened fire, while a fourth suspect surrendered. The IDF said troops were shot at by other Palestinian gunmen and returned fire, hitting targets.
The militant Palestinian Islamic Jihad group and Hamas said their fighters had targeted the troops with gunfire and improvised explosive devices.
The Palestinian health ministry said two civilians, including a 61-year-old woman, were among those killed. Twenty people were also wounded, four of them seriously, it said.
The Palestinian presidency accused Israel of a “massacre” and later announced it had ended co-ordination with Israel on security matters.
A 10th Palestinian was meanwhile shot and killed during a confrontation with Israeli troops in the town of al-Ram, near Jerusalem, as residents protested against the Jenin raid, Palestinian officials said.
At least 30 Palestinians have been killed by Israeli forces in the West Bank so far this year, including militants and civilians, as the military continues operations there.
Last year in the West Bank more than 150 Palestinians were killed, nearly all by Israeli forces. The dead included unarmed civilians, militant gunmen and armed attackers.
A series of attacks by Palestinians and Israeli Arabs targeting Israelis, as well as militant gunfire at troops during arrest raids, meanwhile killed more than 30 people including civilians, police and soldiers. 
