By Nidal al-Mughrabi
GAZA (Reuters) - Israel killed two more Gaza militants on Saturday, raising the death toll in two days of violence to 12 and dozens of rockets fired from Gaza into Israel injured at least four people, Israeli and Palestinian officials said.
Both militants were from the Islamic Jihad group. One of them was killed in a pre-dawn air strike on a vehicle. The other one died as the result of an earlier strike, officials in Gaza said.
After weeks of relative calm, violence along the Israeli-Gaza frontier escalated on Friday when Israel blew up a car in Gaa City, killing two militant leaders. Israel said one of the militants killed on Friday had been involved in plotting a cross-border attack from Egypt.
An Israeli military statement said the latest air strikes had targeted two weapons manufacturing sites. The strikes were launched in response to rocket fire from Gaza that injured four people in Israel, including one man who is reported to be in a serious condition, it added.
The sounds of explosions and rocket fire reverberated across coastal Gaza and parts of southern Israel early on Saturday. Some half a million people were urged to remain indoors and public events were cancelled.
Militant groups in Hamas-ruled Gaza vowed to exact revenge for the slayings. According to the Israeli military, at least 70 rockets have been fired at Israel since Friday, including 10 longer-range Grad rockets intercepted by Israel's "Iron Dome" missile interceptor system.
Islamic Jihad and the Popular Resistance Committees (PRC) claimed responsibility for most of the rockets and mortar shells fired which they also said totaled more than 70.
Israel launched some half a dozen air strikes at militants in Gaza on Friday, killing 10.
Hamas, an Iranian-backed group that refuses to recognize Israel, did not claim responsibility for any of the missile attacks on Israel, and there were no reported civilian fatalities in Gaza, factors which may keep the violence from escalating. Israel says it holds Hamas responsible for any attacks launched from its territory however.
Some half a dozen Palestinians among 16 people wounded in the Israeli attacks have been identified by medics as civilians.
Hamas seized control of Gaza from Palestinian Prime Minister Mahmoud Abbas's Fatah movement in a bloody 2007 coup, two years after Israel pulled its forces out of the territory it had captured in a 1967 war.
(Writing by Allyn Fisher-Ilan; Editing by Andrew Osborn)