JERUSALEM (AP) — Gaza militants resumed their rocket fire toward Israel on Thursday, striking the outskirts of two major cities a day after launching the largest barrage since an eight-day Israeli offensive in late 2012.

Thursday’s attacks set off air-raid sirens in the southern cities of Ashdod and Ashkelon. The rockets landed in open areas, but flew deeper into Israel than Wednesday’s attacks on southern Israeli border towns. There have been no casualties in the latest flare-up.

Gaza militant groups said they resumed their rocket fire in response to what they say are Israeli “provocations” and violations of a cease-fire, including an airstrike that killed three Islamic Jihad militants earlier this week.

Both sides have largely observed a cease-fire that ended the Israeli offensive against rocket launchers in November 2012, in which Israel and Gaza militants engaged in eight days of heavy fighting.

In Wednesday’s attacks, Gaza militants fired more than 40 rockets at Israel in two hours Wednesday. Israel responded swiftly with dozens of airstrikes against militant targets in Gaza. The rocket attacks come during a visit to Israel by British Prime Minister David Cameron, who condemned the attacks.

Israeli Prime Minister Benjamin Netanyahu was to convene his security Cabinet to discuss a further Israeli response, though the expectations were that tensions would calm down in a matter of days rather than spiral into a larger conflagration.

“Our policy in the south is clear. We harm those who try to harm us and respond fiercely to any attack,” Netanyahu said on Thursday. “The terrorist groups in Gaza need to understand that they are dealing with a very determined government and a very strong army.”

The Iranian-backed Islamic Jihad has taken responsibility for the rocket fire, saying it was meant to avenge the deaths of three of its members killed in Tuesday’s airstrike while firing mortars toward Israel.

Gaza’s ruling Hamas movement has not been involved in the latest fighting. But Israeli leaders say they hold the Islamic militant group responsible because it rules the coastal Palestinian territory.

Daoud Shihab, a spokesman for Islamic Jihad, said the group’s attacks were “on behalf of all the Palestinian people.” He also implied that Hamas had given at least tacit approval for the group’s activities, saying “the response of yesterday was blessed by all the factions.”

Sami Abu Zuhri, a Hamas spokesman, said Israel “bears full responsibility” for the escalation.

Gaza militants have fired thousands of rockets and mortar rounds at Israel over the past decade. Attacks have significantly declined since the 2012 offensive, in which Israel carried out some 1,500 airstrikes on targets in Gaza while militants fired 1,500 rockets into Israel.

Israeli aircraft periodically strike militants who launch rockets.