Rockets, mortar rounds and air strikes have hit near the Israeli-Gaza border in the worst violence in almost a year.

Palestinian militants in the Gaza Strip launched more than 90 rockets into southern Israel Saturday, part of a response to Israeli airstrikes that killed 15 militants, including Zohair al-Qaisi, the leader of the Popular Resistance Committees .

Thousands of Palestinian mourners took to the streets of Gaza for the funeral processions of those killed in the Israeli strikes, many chanting “Revenge, revenge!”

Israel said it launched the airstrikes because the PRC was planning an attack on Israel from Egypt. Israeli officials also said at least one Israeli was seriously injured by a militant rocket.

Hamas, which rules the Gaza Strip, has maintained a tacit truce with Israel, but other armed Palestinian groups, like the PRC, regularly fire rockets and mortars across the border, which can spark air strikes in response.

In Gaza, Hamas spokesman Sami Abu Zuhri blamed Israel for the flare-up.

“The Israeli occupation is completely responsible for this escalation and its consequences. The Hamas movement confirms the right of resistance of our people and the factions to defend themselves in facing these crimes.”

Israeli Deputy Foreign Minister Danny Ayalon accused Hamas of forcing Israel's hand.

“”It's unacceptable that a (m) million residents of Israel will be subjected to the mercy of Hamas and all the terror organizations in Gaza. We cannot accept this equation and we will not accept a war of attrition which is what we are seeing.”

The PRC has pledged to avenge its members' deaths.