At least 12 Palestinians, including two boys, a pregnant woman and eight police officers, were killed Sunday by Israeli airstrikes in the war-torn Gaza Strip, hospital authorities said. A strike Sunday morning hit a house in the urban refugee camp of Nuseirat in central Gaza and killed four people, including a couple in their 30s and their 10-year son, according to the nearby Al-Aqsa Martyrs Hospital. The woman had been pregnant with twins, the hospital said. The fourth fatality, a 15-year-old neighbor, was taken to the Awda hospital in Nuseirat. "We were sleeping and got up to the strike of a missile. The strike was strong," said Mahmoud al-Muhtaseb, a neighbor. "There was no prior warning." Another strike Sunday afternoon hit a police vehicle on the south-north Salah al-Din route at the entrance of the central town of Zawaida, the Hamas-run Interior Ministry said. The strike killed eight police officers, including Col. Iyad Ab Yousef, a senior police official in central Gaza, th