Gunmen fired at an Israeli bus travelling near the Egyptian border on Thursday, wounding at least five people, an ambulance service said. Israel Radio says a second bus has been attacked in southern Israel, near the site of the first ambush. Israeli television has reported a gunbattle in the area. . The first bus was attacked on Israel's Highway 12, a secluded desert road, about 30 km (18 miles) north of the Red Sea resort city of Eilat. The road passes within metres of the border line with Egypt. Security sources in Sinai say that the shots were fired from the Israeli side of the border. The Israeli newspaper Haaretz reported that reports indicated that the shots were fired from a car that was following the bus on an Israeli road. Israel Radio said several gunmen in a car ambushed the civilian bus. The Magen David Adom ambulance service reported at least five passengers were wounded. "It was a terrorist attack," an Israel Radio reporter in the area said. Television pictures showed several bullet holes in the bus windscreen and broken windows along its side. Egypt recently stepped up security activity in the Sinai desert, which borders Israel and the Gaza Strip. Egyptian security sources said on Tuesday that an army crackdown on armed groups in the northern Sinai had netted four Islamist militants as they prepared to blow up a gas pipeline. Intelligence officials in Egypt said militant groups in the Sinai were making use of a security vacuum left by the overthrow of President Hosni Mubarak in February.