Israel's air force hit Islamic Jihad targets in Gaza for a second day on Wednesday and Palestinian fighters in the enclave launched rockets across the border, sending residents to shelter as far away as Tel Aviv.
The second round of cross-border fire in a week came after Israel launched strikes on Tuesday against three Islamic Jihad commanders it said had planned attacks against Israelis, following months of escalating violence.
Cairo, which has mediated a truce in previous rounds of fighting, had begun mediating a ceasefire, Islamic Jihad spokesman Dawoud Shehab told Reuters, but there was no immediate confirmation from the Israeli side.
The Israeli military said it was attacking rocket sites preemptively as blasts rocked different points including what witnesses described as a training camp in the northern part of the Gaza Strip and an open area in the south.
At least four people were killed, Gaza medical officials said. They were claimed by the armed wing of the Popular Front for the Liberation of Palestine PFLP.
Minutes after the strikes, sirens sounded in Israel -- initially among border communities but soon also in and around the commercial capital Tel Aviv, 60 km (37 miles) north of Gaza.
More than 270 rockets were fired within two hours, a military spokesman said. The joint command of Gaza's armed groups, which includes Islamic Jihad and the enclave's Hamas rulers, claimed responsibility for the salvoes.
However, Israeli military officials said they had seen no signs that Hamas, which is believed to have hundreds of rockets in its arsenal, had fired any missiles itself.
They said Israeli strikes were directed only at targets linked to the smaller Islamic Jihad group, an Iranian-based militant organization based in Gaza which has been increasingly active in the West Bank for the past year.
‘Prepared for escalation’
Multiple trails could be seen ascending in Gaza as rockets were launched. Mid-air explosions signaled interceptions by Israel's Iron Dome aerial defense system and there were no reports of casualties in Israel.
"We are prepared for escalation," Israeli Prime Minister Benjamin Netanyahu told council heads in the towns near Gaza, according to a statement.
In total, 20 Palestinians, including at least five women and five children, as well as three senior Islamic Jihad commanders, and four PFLP gunmen have been killed since Israel conducted a series of pre-dawn strikes on Tuesday. Among the dead on Wednesday was a 10 year-old girl.
The joint command of militants said the rocket salvoes were a retaliation for the Israeli strikes, which it described as "a savage and treacherous bombardment of civilian houses that led to several innocent martyrs."
Last week, Islamic Jihad fired more than 100 rockets across the border and Israeli jets hit targets in Gaza in a hours-long exchange following the death of an Islamic Jihad hunger striker in Israeli custody.
Even before Wednesday's rocket barrage began, as many as 30% of residents of Israeli border communities had been evacuated as a precaution, municipal head Gadi Yarkoni told Kan radio.
In Gaza, businesses and schools remained closed, Israel kept its two commercial and people crossings with Gaza closed. The move would stop the entry of goods, fuel and humanitarian aid as well as patients, who receive treatment in hospitals in the West Bank and Israel.
Earlier on Wednesday, Israeli forces killed two Palestinians who opened fire on them in Qabatiya, in the occupied West Bank. Islamic Jihad claimed the two as members.
The army said the two Palestinians fired on troops from a car and were shot dead. An assault rifle was recovered from the vehicle, it said, adding that there were no Israeli casualties.
