The Israeli air force has launched a series of air raids on the Gaza Strip, hours after the bodies of three settlers were found in the occupied West Bank.

The Israeli military said it launched 34 raids in the early hours of Tuesday, in response to 20 rockets fired into Israel from the strip.

A Palestinian was also shot dead on Tuesday in an Israeli operation in Jenin, in the West Bank. The Israeli military said the dead man was a member of Hamas and was attempting to throw a grenade, although this information cannot be independently verified.

The attacks came hours after the Israeli prime minister, Benjamin Netanyahu, promised that the Gaza-based group Hamas "will pay" after the discovery of the young settlers' bodies near the West Bank village of Halhoul on Monday.

They disappeared on June 12 while hitchhiking home from a religious school in Kfar Etzion, an illegal settlement between Bethlehem and Hebron, and were last heard in a brief emergency call to police.

AJ+ explains: Israeli Settlements

Their disappearance set off the largest military operation in the West Bank since the end of the second Intifada. More than 400 Palestinians were arrested in the 18-day search, thousands of homes raided and five people killed by Israeli gunfire.

Hamas blamed

On Monday night Israel demolished the homes of Marwan Qawasmeh and Amer Abu Aisha, two Hebron-area residents who the Israeli government has named as suspects.

The use of punitive demolitions revived a practice that was almost entirely discontinued in 2005.

The Israeli security cabinet also held an emergency meeting on Monday night, which ended with no major decisions on further actions, according to a government source. The cabinet will reconvene on Tuesday.

Some politicians have called for harsher steps against Hamas, including targeted assassinations. "I don’t know how many leaders of Hamas will remain alive after tonight," said Tzachi Hanegbi, the deputy foreign minister.

The group dismissed the accusations in a statement, calling them propaganda.

"The (Israeli) occupation's accusations against us deserve no comment, because the problem is with the occupation which continues its crimes and escalation," Sami Abu Zuhri, a Hamas spokesman, told Al Jazeera.

"The occupation shoulders the responsibility for any escalation."

The PLO's Hanan Ashrawi told Al Jazeera that the "Israeli escalation already took place, and now they have an excuse of further escalation."

Tuesday's events prompted the United Nations' human rights office to urge Israelis and Palestinians to "exercise maximum restraint and to prevent the situation from worsening further".

"We reiterate our call for strict adherence to international law by all relevant actors to avoid further loss of life, injuries and negative impact on human rights," UN human rights spokeswoman Ravina Shamdasani said in Geneva.

"We urge all parties to refrain from punishing individuals for offences they have not personally committed or by imposing collective penalties."