Hamas's victory in the Palestinian Authority elections and the inauguration of the new Palestinian Legislative Council over the weekend have sparked a sharp increase in the number of security warnings with the Shin Bet (Israel Security Agency) on Sunday recording 76 - compared to around 50 two weeks ago. A security official told The Jerusalem Post that the Hamas takeover of the PA has motivated Islamic Jihad to become the vanguard of the Palestinian struggle by escalating its terror activity. "Islamic Jihad sees the possibility that Hamas will decrease its terror activity as an opportunity to take over and lead the fight against Israel." Discerning the new terror wave, the IDF stepped up its activity in the West Bank and Gaza on Sunday and launched a widespread operation in the Balata refugee camp in Nablus aimed at cracking the local terror infrastructure. Four Palestinians involved in terror activities were killed in separate incidents in the West Bank and Gaza on Sunday. Two were hit by helicopter-launched missiles while attempting to place a bomb near the southern Gaza security fence. Two others were shot during clashes with soldiers operating in the Balata refugee camp in Nablus, where a widescale IDF operation is underway to rout out terrorists planning to launch attacks. In the early morning, two Gazans were spotted in a restricted area 30 meters from the security fence south of the Kissufim Crossing. An air force helicopter on patrol was alerted and fired two missiles killing the two bomb carriers. They were later identified as Bilal Najer, 18, and Osama Breis, 20, of Rafah, both members of the Popular Resistance Committee. Hours later, Palestinian police informed the army that a bomb was found near the site where the two were hit. Two Palestinians were shot and killed as heavy gun battles erupted during the army's "Northern Lights" operation in the Balata camp, aimed at damaging the terror infrastructure there. Nine Palestinians were wounded in the exchange of fire with soldiers. The Palestinian media claimed one of the wounded was Dr. Anan Athira, a female doctor who reportedly suffered a head injury while tending to patients. Her condition was later listed as stable. Two others wounded were identified as Muhammad Habash, 15 and Ramzi Salah, 17. However, a Central Command officer said all those killed or wounded were either armed or attempting to detonate bombs near troops. Paratroopers and soldiers of the Haruv Battalion under the command of Samaria district commander Col. Yuval Bazak entered the camp late Saturday night to forestall mounting plans by terrorists to launch attacks. The operation is expected to continue for a number of days. "Intensive IDF operations conducted in recent weeks to nab fugitives in northern Samaria have weakened the terrorist infrastructure there and forced them to transfer their anti-Israel activities to the Nablus area," an IDF officer told The Jerusalem Post. Four explosive belts caught by soldiers manning the Awarta checkpoint outside of Nablus in recent weeks were part of these attempts, the officer said. The troops encountered fierce resistance on entering the camp. Explosives were set off near soldiers and fierce exchanges of gunfire erupted. Soldiers also had to contend with mobs throwing stones and firebombs. During the day, security forces arrested a wanted Fatah terrorist in the camp and an IDF bulldozer demolished a home where soldiers believed other wanted men were hiding. Elsewhere in the West Bank, troops arrested an Islamic Jihad fugitive in Ilar north of Tulkarm. At a checkpoint at Salem northwest of Jenin, soldiers arrested a Palestinian caught carrying two knives.