A tense quiet settled in over southern Israel on Thursday as a ceasefire seemed to go into effect following three days of intense fighting between the IDF and Palestinian terror groups in the Gaza Strip.Seven rockets pounded Israel early Thursday morning, in addition to one that was intercepted by the Iron Dome counter-rocket defense system near Ashkelon. In total, the IDF said that 130 rockets were fired into Israel since Monday.In the afternoon, the IDF raised the level of alert along the Egyptian border and ordered residents of towns located near the border to remain in their homes and to lock their doors. Rapid response teams were scrambled to the towns and the IDF reinforced forces nearby out of concern that terrorists were planning another attack from the Sinai Peninsula. By the evening, the IDF lowered the level of alert but kept Road 12 – along the border – closed due to a general concern over future attacks. On Wednesday, the Air Force attacked a motorbike in Rafah, seriously injuring a top global jihad operative who the IDF said was planning another attack against Israel from the Sinai.Meanwhile Thursday, the IDF said that it had noticed an increase in the use of cellular phones to detonate roadside bombs in the West Bank. The use of phones, the military said, had declined in recent years but suddenly picked up in late 2011. The IDF said that it also noticed an improvement in the camouflage used to hide the bombs.The most recent attack with cellular detonation was in April, when a bomb exploded next to an IDF vehicle near the West Bank town of Yatta near Hebron. No one was injured in the attack. Last week, two residents of Yatta were indicted for manufacturing explosive devices and planting bombs in the Hebron area.