(CNN) -- As dozens of Palestinian rockets rained down on southern Israel, the country's air force carried out new raids on positions in Gaza on Wednesday. Two days of air strikes have so far killed three Palestinians.
Attacks and counter attacks between the two sides are a frequent occurrence but appear to have escalated in the past two days.
On Tuesday night, the Israeli military said its aircraft had targeted two rocket-launching squads in northern Gaza as they prepared to fire rockets into southern Israel. That attack killed two militants from Al-Qassam group, the military wing of Hamas, and wounded two others.
But the barrage of rockets continued, with more than 65 fired from Gaza in an eight-hour period, the military said Wednesday morning.
Israeli aircraft struck Gaza again early Wednesday, killing one person and seriously wounding nine others, said Ashraf al-Qidra, the spokesman of the health ministry in Gaza.
The strike targeted a rocket-launching site in northern Gaza, the IDF said, adding that its tanks had also shelled "terrorist targets."
The Palestinian rocket attacks wounded three Thai workers in Israel, hospital officials said..
Israeli areas around Gaza are under heightened alert amid fears that more rockets could be launched.
The violence came after the emir of Qatar, Sheikh Hamad bin Khalifa al-Thani, visited Gaza on Tuesday, becoming the first head of state to visit since Egypt and Israel instituted a blockade in 2007.
Annual Qatari aid to Palestinians in Gaza will increase from $250 million to $400 million, Hamas Prime Minister Ismail Haniya told reporters in Khan Younis in southern Gaza.
In Washington, State Department Spokeswoman Victoria Nuland said U.S. officials "share Qatar's deep concern for the welfare of the Palestinian people, including those residing in Gaza."
But she expressed continuing concern over the "destabilizing role" of Hamas, which has governed Gaza since 2007.
CNN's Michael Schwartz and Kareem Khadder contributed to this report.
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