On Saturday, Israel's army announced that it had carried out retaliatory airstrikes after about 50 rockets were fired from the Palestinian enclave of Gaza earlier in the day. There were no reports of casualties from the attacks, with dozens of rockets reportedly intercepted by air defenses.

The flare-up comes after four Palestinians in the Gaza strip were killed on Friday, as protests erupted along the Israeli border. Two of those killed were said to be Hamas militants.

The Health Ministry in Gaza confirmed the deaths, saying two people had been shot dead and the two Hamas fighters were killed in an airstrike.

Israel's army reported that the airstrike was launched in retaliation for a shooting incident on the border that left two Israeli soldiers wounded.

The incidents represent a new escalation since a cessation of hostilities was mediated by Egypt a month ago, after a rocket that hit a house in central Israel reignited tensions between Palestinians and Israelis.

An Israeli army spokeswoman said that about 5,200 Palestinians had taken part in Friday's daylong demonstrations. More than 50 Palestinians suffered various injuries during the protests.

Read more: Gaza Strip: Hamas facing growing pushback

Hamas pledges response

Gaza's rulers accused Israel of not honoring the deal that was brokered by Egypt, which the militants had hoped would lead to Israel scaling back the blockade imposed on Gaza in 2007.

Hamas also accused Israel of delaying the transfer of Qatari money for Gaza’s cash-strapped public institutions in the territory and not helping to ease the territory’s power shortage.

Israel, which seized Gaza in the 1967 Middle East War and pulled out its troops and settlers in 2005, claims that the blockade is necessary to stop weapons from reaching Hamas.

The militant group has fought three wars with Israel and fired thousands of rockets at the country in the past decade.

Hamas pledged on Friday to respond to what it called "Israeli aggression."

tj,jcg/bw (AFP, AP, Reuters)

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