During the operation, IDF soldiers killed two Hamas activists, who according to the Palestinians attempted to push the troops back.
The Palestinian news agency Ramatan quoted a Hamas source who claimed that one of the gunmen killed was among those who planned Gilad Shalit's kidnapping. The agency reported that the source refused to say which of the gunmen he was referring to, but according to estimations, the man is Ashraf al-Muashar, a commander in Hamas' military wing and one of the commanders of the organization's terror unit.
A Palestinian security source told Ynet that he could not confirm the report.
The soldiers, who began operating on Tuesday following information received from the Shin Bet, uncovered a 12-meter deep tunnel used for smuggling weapons and another two tunnel pits.
The forces continued to operate in the area over the night and in the morning, and in one of the incidents the soldiers opened fire at two gunmen who began approaching them.
"Wherever there is terror, we will be there," sources in the Southern Command stated.
IDF forces recently uncovered 15 underground tunnels, some of them destined to be used for terror attacks against Israeli targets. IDF officials admitted, however, that the issue of underground tunnels required a more expanded operation.
Palestinian sources reported Wednesday morning that during the operation IDF forces besieged the Rafah crossing and members of Force 17, the Palestinian presidential guard, which has been in control of the crossing since Corporal Gilad Shalit was kidnapped.
'250 terrorists killed since kidnapping'
The crossing remained closed in recent months, excluding several days in which is was opened, in a bid to ease the Palestinians' distress. In the past few weeks, the armed organizations threatened that if a solution is not found, and the crossing is not operated, they will forcefully open it.
In the meantime, the Southern Command is also preparing to boost its operation in the northern Strip, mainly against the infrastructures used to launch Qassam rockets.
"Since Gilad Shalit's kidnapping, more than 250 terrorists have been killed," a military source said. "This pressure will continue and will even get stronger."
Israeli officials claimed that the Rafah crossing and the Philadelphi route have turned into the main center for smuggling weapons into the Strip since the disengagement.
According to reports by Israeli security sources, the Palestinians have managed to smuggle great amounts of weapons and ammunition, including antitank missiles, through the route.
Ali Waked contributed to the report