Palestinian terrorists lightly wounded four Israelis, including a pregnant woman, in a drive-by shooting Tuesday between Nili and Na'aleh, east of the Green Line and north of Modi'in. The driver, 35, was shot in the shoulder but kept driving to Na'aleh, where he reported the attack. The three passengers, including a 30-year-old pregnant woman and another woman, 25, were lightly wounded by shrapnel. The four were evacuated to Sheba Hospital in Tel Hashomer. An offshoot of the Aksa Martyrs Brigades claimed responsibility for the attack. The attackers escaped. Last week, a 30-year-old Israeli was moderately wounded in a shooting attack near Karnei Shomron after Palestinians in a car fired at a hitchhiking post. Even though Tuesday's shooting attack was not far from Route 443, a main highway that connects Jerusalem and Modi'in, security sources said drivers need not be overly concerned. "This is an important road and we do everything we can to prevent terrorism from reaching it," an IDF officer in Central Command said. Over the weekend, the IDF arrested 20 Palestinians on suspicion of throwing rocks and Molotov cocktails at cars on Route 443. Also Tuesday, undercover border policemen shot and killed an Aksa Martyrs Brigades operative near Jenin. Ahmed Hanaishe was driving between Jenin and Kabatiya when his car was blocked by a vehicle carrying border policemen, who shot him. According to Palestinian sources, Hanaishe belonged to Islamic Jihad but had been working for the Fatah-affiliated Aksa Martyrs Brigades. AP contributed to this report.