PRC chief, Zohair al-Qaisi, and fellow member Mahmud Hanani were killed in a srike on their car Gaza / Ramallah – Mohammed Habib / Sona Al-Deek The death toll after a series of Israeli airstrikes on the Gaza strip has risen to 12 Palestinians, while another 20 were wounded. Egyptian Ambassador to the Palestinian Authority Yasser Osman condemned \"the Israeli aggression against the Palestinians,\" and \"Israel\'s violations of the ceasefire agreement\".
The Ezz al-Din al-Qassam Brigades, Hamas\' military wing, threatened on Friday to \"retaliate over Israel\'s crimes against the rights of the Palestinian people and the commanders of the resistance in Gaza\".
Hamas\' Interior Ministry said that the security forces\' headquarters in Gaza City have been evacuated over concerns of a possible Israeli Air Force strike.
A senior Palestinian leader Zuhair al-Qaisi, the secretary-general of the Popular Resistance Committees (PRC), was killed in the first strike by Israeli warplanes, along with another senior member of the PRC, Mahmoud Hannani. The PRC is known to have carried out rocket attacks against Israel, and the Israelis say al-Qaisi was targeted because he was planning an attack.
Earlier, two members of the al-Quds Brigades, the military wing of Islamic Jihad, were killed on Friday evening in a Zionist bombing that targeted them in Shijaia district.
Gaza emergency services spokesman Adham Abu Selmeya told Arabstoday that the strike hit the victims in al-Shujaeha neighborhood, east Gaza City. The two were killed on the spot and their bodies were dismembered by the missile, Abu Salema added.
Al-Quds Brigades said in a statement obtained by Arabstoday that “the blood of martyrs will not be shed in vain and will follow the occupiers everywhere”. The statement added that the resistance movement will continue until all Palestinian soil is freed.
Meanwhile, Nasser Saladin Brigades, the military wing of the PRC, announced its refusal to call a ceasefire, asking its fighters to fiercely respond to the assassination of its Secretary General Zuhair Al-Qaisi, happened in Gaza on Friday afternoon. Saladin Brigades also said in a statement that sacrifice and bloodshed are the only way towards freeing Al-Aqsa and the whole country.
They added: “The Zionist enemy has opened the doors of hell for itself by killing the Secretary General,” declaring that they will take revenge for their martyrs and that the response will equal “this heinous crime”.
Abu Mujahed, the spokesperson of the Committees, has said that the Israeli occupation first breached the truce and it should bear the consequences of such a decision. Mujahed also asked all the factions to take responsibilities and to suspend “the accursed truce,” confirming that their response will come in the next hours.
The Palestinian resistance started to strike targets adjacent to the Gaza strip.  
The National Resistance Brigades claimed responsibility for firing 107 rockets on the settlements adjacent to northern Gaza, as an initial response.
Al-Aqsa Brigades launched its campaign “The South Earthquake” by firing four rockets towards different destinations.
Meanwhile, the Nasser Saladin Brigades claimed responsibility for bombing the town of Azata, east of Gaza, with a rocket.
For its part, Israel denounced the fall of three rockets on an open space in Negev on Friday evening.
Earlier, two mortar shells landed on the western Negev causing no casualties or damage, while a senior officer in the Israeli army said that Israel will not allow Hamas to continue shelling the south of the country and that the army will follow the necessary procedures.
Earlier on Friday afternoon, Israeli military sources admitted the assassination of the Popular Resistance Committees  Secretary General, Zuhair Al-Qaisi, and that of the released detainee Mahmoud Hanani, originally from Nablus but exiled to the Gaza Strip, during an attack against their car on Friday.
The sources told the occupation radio that the assassination of Al-Qaisi, whom Israel considered as one of the most dangerous figures in Gaza, was meant to convey a message to anyone who tries to harm the security of the Jewish state.
Israeli sources added that they will not stop targeting individuals who spread and profess violence, explaining that the army and the security services will make “Palestinian terrorists”- as they called them - pay a heavy price.
The sources blamed on Hamas the escalation of violence on the border of the Gaza strip, demanding that the political party keep the situation under, control “if it really wants to continue to ruling Gaza”.
Immediately after the attack, the spokesperson for the emergency service told Arabstoday that “Two martyrs arrived at the hospital torn into parts and beheaded, while two others reported minor injuries”.
Witnesses reported that the car was hit while it was travelling near the old Palestine TV building.
The blast set a small metallic blue car ablaze. At least two of the victims were inside the vehicle when the explosion occurred, witnesses said. Reuters television footage showed one charred body being carried away from the scene.
Mahmoud Hanani was the first of the 1000 Palestinian prisoners freed in the deal to be killed by an Israeli strike.
Israel often launches retaliatory attacks after missiles are fired at its territory from Gaza, which is run by the Islamist group Hamas.
Al-Qessi was elected chief of the PRC last August after Israel killed his predecessor in an air strike in the southern Gazan town of Rafah.
Israel launched that raid after accusing the PRC of staging attacks along its border with Egypt that killed seven Israelis.