Israeli troops rolled into southern Gaza early Thursday, sparking fierce fighting with local fighters and killing at least seven Palestinians, among them five members of the same family whose house was shelled, hospital officials said, according to dpa. A seventh Palestinian, a Hamas fighter, was also killed and two others injured in eastern Gaza City, as Israel launched at least four airstrikes throughout the Strip at members and buildings of fighter factions involved in daily rocket attacks against it. An Israeli army spokeswoman said the incursion into the south-eastern outskirts of the town of Khan Younis was a "routine" operation against the rocket fire from the Strip. She said fighters opened fire, threw grenades and fired anti-tank missiles at the force, which responded by calling in air support and with tank shelling, including at a house from which gunmen were firing at the troops. Five members of the Fayyad family were killed in the shelling of the house. At least three of them were civilians - the mother, her 18-year-old daughter and a 16-year-old son. Another son, Sami Fayyad, 23, who was also killed, was identified as a fighter of the radical Islamic Jihad faction, which has taken the forefront in the rocket attacks against Israel during the past months. The body of Mohammad Fayyad, believed to be the father of the family, was also pulled from the wreckage of the house in the early afternoon. At least two other fighters of the Islamic Hamas movement ruling Gaza were also killed in the fighting, and 25 people injured. Most of them were fighters, but a two-year-old toddler, the daughter of the Islamic Jihad fighter, was among the severely wounded, Nasser hospital in Khan Younis said. She was clinically dead and on a life support machine. The fighting came as Palestinian fighters fired a 122-milimetre Russian-made Katyusha missile at a residential neighbourhood in the southern Israeli port city of Ashqelon, the Israeli military said. The fighters also fired at least five other, Gaza-made Qassam and al-Quds rockets at Israel, as well as mortar shells. Meanwhile, Israeli F-16 fighter jets bombed several buildings in Gaza City and elsewhere in the Strip Thursday afternoon. An Israeli military spokeswoman confirmed four airstrikes on a rocket warehouse of the Islamic Jihad, a house of an Islamic Jihad activist, a Hamas building and an armed man respectively. No one was injured in the first three strikes, as the buildings had been evacuated, but they were said to be completely destroyed. The escalation of violence in Gaza comes days before US President George W Bush is due to arrive in the region for a three-day visit aimed at advancing the Israeli-Palestinian peace process, which Israeli Prime Minister Ehud Olmert and Palestinian President Mahmoud Abbas pledged in Annapolis, Maryland last year to revive after a seven-year freeze. Bush's three-day visit to Israel and the West Bank next week is the first since he took office. Abbas and Olmert agreed at the November 27 Annapolis conference to strive for a peace deal before the end of his term in January 2009. But in addition to the violence in Gaza, Israeli-Palestinian talks have thus far been overshadowed by a dispute over Israeli construction in two Jewish settlements in southern and east of Jerusalem - Har Homa and Ma'aleh Adumim. Olmert made an unannounced visit to Aqaba, Jordan Thursday for talks with King Abdullah preparing for the Bush visit, a day after the Jordan king met also Abbas. In a news conference with Egyptian President Hosny Mubarak Wednesday, Abbas called the Israeli construction plans a "real hurdle" on the path to constructive negotiations, which he said would be addressed by Bush during his visit. But he said Olmert had promised to "send a message to all Israeli ministries and ask them to stop any settlement work." Olmert said in an interview Friday that Israel would continue to build in Ma'aleh Adumim, which he called an "indivisible" part of Jerusalem, but pledged to freeze settlement construction elsewhere.