IDF troops shot and killed three Palestinians over the weekend during operations in the West Bank and the Gaza Strip. On Saturday, the IDF opened fire at three Palestinians, spotted near the Gaza security fence south of the Karni Crossing. One of the Palestinians was killed and the two others were wounded and taken for questioning. The army said the soldiers fired when the Palestinians appeared to plant an explosive device along the border fence. The Southern Command was investigating the incident and had not ruled out the possibility that the three were not terrorists but were trying to cross illegally into Israel in search of work. "Every time someone approaches the fence we categorize it as a potential terror attack," explained an officer in the Southern Command. "Our mission is to stop anyone who comes close to the fence." According to the officer, the IDF has noticed a slight increase lately in the number of attempts by Palestinians to infiltrate into Israel. Earlier Saturday, five Palestinians were caught after they had infiltrated into Israel near Kibbutz Be'eri. "This is a complicated mission since sometimes they are terrorists and sometimes they are civilians sent by terrorists to test us and to collect intelligence," explained a military source. "We view each incident as a potential terror attack and cannot afford to take any chances." On Friday, two Palestinians were killed during one of two gunfights between IDF troops and Palestinian gunmen near Jenin. The first exchange of fire broke out after soldiers entered the village of Kafr Dan, local residents said. Two Palestinians were killed, an Islamic Jihad gunman and a civilian, doctors said. Several were wounded. Earlier Friday evening, the IAF fired two missiles at Palestinian rocket launchers in the northern Gaza Strip shortly after three rockets and 12 mortars were fired toward Israel. The missiles missed the launching squad that was on its way back from firing rockets toward Israel. No one was wounded, Hamas said. AP contributed to the report.