By Rami Ayyub
TEL AVIV (Reuters) - Israeli aircraft struck Hamas sites in Gaza late on Saturday, the military said, in an escalation of hostilities after earlier cross-border gunfire seriously injured an Israeli soldier and wounded 41 Palestinians, including two critically.
The injuries came during a Gaza protest organised by the enclave's Islamist rulers Hamas and other factions in support of Jerusalem, where Palestinian clashes with Israeli police helped spark an 11-day Israel-Hamas conflict in May.
Hundreds of Palestinians gathered near the Strip's heavily fortified border, where some tried to scale the border fence and others threw explosives towards Israeli troops, the Israeli military said.
"IDF (Israeli military) troops responded with riot dispersal means, including when necessary live fire," it said in a statement.
Among the two Palestinians critically injured was a 13-year-old boy who was shot in the head, Gaza's health ministry said. It described most of the other injuries as moderate, including gun shots to limbs, backs and abdomens.
Cross-border fire from Gaza seriously wounded an Israeli border police soldier, who is in hospital receiving medical treatment, the military said. There was no claim of responsibility for the Gaza gunfire.
In response to the soldier's shooting, Israeli "fighter jets have struck four weapons storage and manufacturing sites belonging to" Hamas, the military said. There were no immediate reports of injuries or damage.
Bracing for more hostilities, the military said it had sent additional forces to the Gaza border area. Israeli media reported the military had increased deployment of its Iron Dome anti-missile system.
The violence follows an Israeli announcement of a resumption of Qatari aid to Gaza, a move seen as bolstering a fragile Egyptian-mediated truce to the May fighting.
Just days before that announcement, Gaza militants launched a rocket towards Israel that was shot down by the Iron Dome, in the first such attack since the truce.
Palestinians have also sporadically launched fire-laden balloons towards Israel since the fighting, drawing Israeli strikes on Hamas sites.
Hamas spokesman Fawzi Barhoum said Saturday's air strikes showed Israel was "trying to cover up its failure and disappointment in front of the steadfastness of our people and their valiant resistance."
At least 250 Palestinians and 13 in Israel were killed in the May conflict, in which Gaza militants fired rockets towards Israeli cities and Israel carried out air strikes across the coastal enclave.
Israel keeps Gaza under a blockade, tightly restricting movement out of the territory that is home to 2 million Palestinians. Egypt also maintains restrictions on the enclave. Both cite threats from Hamas for the restrictions.