For the second time in three days, security officials caught a would-be suicide bomber Wednesday en route to central Israel, raising concerns over a new wave of terrorist attacks, security officials said. Later Wednesday, Defense Minister Amir Peretz ordered a general closure of the West Bank and the Gaza Strip through Saturday night because of an increase in intelligence warnings of impending terror attacks. The terror suspect was apprehended at a construction site in Hod Hasharon near Tel Aviv, hours after police went on red alert in the area in an effort to seize the would-be bomber before he struck. The alert, which began in the late morning and continued until the arrest in the early afternoon, caused massive traffic jams as police set up roadblocks on major highways. With traffic at a standstill and the midday summer heat in full force, police began distributing bottles of cold water to stuck motorists. Summer camps and day care centers in nearby communities were told to stay open later than usual since parents could not get there in time to pick up their kids, while security at places of entertainment was heightened. Later in the afternoon, security officials arrested a man in nearby Kafr Kassem suspected of helping the would-be bomber. The arrests came two days after capital police seized a Palestinian carrying five kilograms of explosives in downtown Jerusalem. Police said that man was about to blow himself up. The two foiled attacks heightened concern that terrorist organizations are planning a new wave of suicide bombings in major cities, to open a third front as the military faces off against Hamas in Gaza and Hizbullah in Lebanon. Before dawn Wednesday, IDF troops raided Nablus, surrounding a prison where a group of wanted gunmen was hiding. The soldiers demanded that those inside surrender, then began to bulldoze the compound. They then killed at least three of those inside in a shootout. The army said the three men belonged to a cell with ties to Hizbullah that was planning terror attacks. A fourth gunmen died later of his wounds. Two Arab journalists, including a correspondent for Al-Jazeera TV, were lightly wounded during the clash, The Associated Press reported. The army arrested an unspecified number of wanted men during the operation. In the evening, a man throwing rocks at IDF troops in the city was also killed, Palestinian eyewitnesses said. The army said it had not employed live fire in the incident and was unaware of any causalities. In Gaza Wednesday, soldiers killed eight gunmen during a joint land and air raid on a Mughazi refugee camp in the central Strip. Five soldiers were wounded, including two moderately, during the day-long operation, the army said. The camp, which has 22,000 residents, is about 1 km from the Israeli border, across from the Palestinian town of Deir al-Balah. Violence continued in the camp in the evening, when an IAF aircraft twice opened fire at a group of gunmen, killing at least one and wounding about two dozen others, including an unconfirmed number of civilians. More than 100 Palestinians - the vast majority of them gunmen - have been killed in Gaza since the army began its incursions to flush out terrorists and to stop rocket attacks. Despite the army raids, Palestinians continued to fire Kassam rockets into Israel, including one that landed Wednesday night in in an open field in Ashkelon. There were no immediate reports of injuries or damage. Palestinians also fired a more sophisticated rocket at Sderot, the army said.