The Israeli army killed four Palestinians on Thursday, including a 75-year-old woman, one day after the Gaza Strip suffered its deadliest violence since Israel launched its offensive last month.

Despite a high death toll in Gaza, with 23 people killed on Wednesday alone, the world's attention has been focused on Lebanon, where Israeli forces have been fighting Hezbollah guerrillas since July 12.

Israel's army and air force have been attacking the Gaza Strip to try to stop militants from firing rockets at southern Israel. The Israeli operation began after Hamas-linked militants killed two soldiers and captured a third in a cross-border raid on a military outpost on June 25.

CountryWatch: Israel

On Thursday, the 75-year-old woman was hit by shrapnel from an Israeli tank shell fired at her house near the town of Jebaliya, Palestinian security officials said. The army said it had no immediate comment.

The air force fired missiles at eastern Gaza City, killing a Hamas militant and wounding 14 others. The army said the attack hit a group of armed men before they could fire at troops.

Two Palestinians later died of their wounds, a man hit by an airstrike in eastern Gaza City, and 18-year-old Ahmed Ismail Abu Amsha, who was hit when a tank shell fell near his house in northern Gaza, medics said. Three of Amsha's family members were lightly injured.

A tank shell hit a factory that makes paper towels in eastern Gaza City, setting it on fire. No injuries were reported, but the factory was severely damaged, a civil defense official said.

EU External Relations Commissioner Benita Ferrero Waldner and Erkki Tuomioja, Finland's foreign minister, visited Shifa Hospital in Gaza City on Thursday but did not meet with Palestinian government officials. Later, at a news conference in Tel Aviv, Tuomioja said of the high casualties in Gaza, "that kind of violence must stop and is not acceptable."

On Wednesday, Israel aircraft, tanks, and artillery supported bulldozers flattened orchards and greenhouses to deprive cover to militants firing rockets into Israel, the army said. But Gaza militants fired two homemade rockets at the Israeli town of Sderot on Thursday.

The 23 Palestinians killed on Wednesday included 16 militants; two unidentified men; a mother and her 5-year-old and eight-month-old daughters; a 3-year-old girl; and a man who was believed to be mentally handicapped.

Complete coverage of the Mideast Meltdown is available in FOXNews.com's Mideast Center.