The Israel Air Force launched an aerial strike on the Gaza Strip on Tuesday night, the first such attack since Israel and the coastal territory's Hamas rulers declared a truce after Operation Pillar of Defense last November.

The strike near the northern Gaza town of Beit Lahiya came after militants in the Gaza Strip fired two mortar shells at the western Negev earlier on Tuesday.

Tuesday's events follow a number of incidents that breached the understandings that were set following Operation Pillar of Defense, and which brought relative peace to the south.

Responding to the fire from Gaza, Defense Minister Moshe Ya'alon stated Wednesday morning: "We hold Hamas responsible for everything fired from the Gaza Strip into Israel. We will under no circumstances tolerate a routine trickling in of fire on out citizens or our forces."

During February a rocket was fired for the first time at Ashkelon, with no damage or casualties. Following the fire, the IDF Chief of Staff Lt. Gen. Benny Gantz defined the incident as "severe," but added that in his opinion, the aims of Operation Pillar of Defense had been achieved. At the beginning of March, during fire from the Gaza Strip, a bullet hit the windscreen of a jeep carrying the commander of the Northern Gaza Territorial Brigade. There were no casualties during this incident but the vehicle was damaged.

During U.S President Barack Obama's visit two weeks ago, four rockets were fired into Israel. A house in Sderot was damaged and there were several victims of shock. After the incident, the crossings into Gaza were closed for a week and were only opened recently. Meanwhile, the Gazan's fishing area was reduced from six nautical miles to three.

As stated, the IDF carried out aerial strikes during the evening for the first time since the end of Operation Pillar of Defense and the understandings that were reached at the time. This action comes a day after three mortar shells were launched at Israel – including one that landed in an open area in the Eshkol Regional Council, and two others that landed near the border on the Palestinian side.

A mortar shell fired from Syria landed in the Israeli Golan Heights on Tuesday evening, and an IDF patrol came under gunfire in a separate area of the northern territory.

IDF tanks fired shells into Syria in response to the gunfire, which struck near a patrol in Tel Hazeka. There was no word yet of casualties on the Syrian side. The same area has come under fire from Syria in the past.

Shrapnel from the mortar shell hit an IDF jeep touring in the central Golan Heights, near Tel Fares. The jeep sustained light damage, but no casualties were reported in either the shell or light fire incident. It is not yet clear whether the fire was shot by Syria rebels or forces loyal to President Bashar Assad, and whether it was directed at the IDF force or strayed from the fighting north of the border.

Last week, IDF troops fired a retaliatory missile into Syrian territory near the Golan Heights and destroyed a machinegun position, in response to two security incidents in less than 24 hours. At least two Syrian soldiers were wounded from that Israeli fire.

Defense Minister Moshe Ya'alon conducted his first tour to the Golan border with Syria earlier Tuesday, accompanied by IDF Chief of Staff Lt. Gen. Benny Gantz and GOC Northern Command Maj. Gen. Yair Golan in his visit to various military bases in the north, including the one hit by cross-border fire from Syria last week.

Golan briefed Ya'alon on IDF protocols involving cross-border fire during their tour, saying that the military only responds when the shooting is continual and after a warning is delivered to UN peacekeeping forces.

Ya'alon, meanwhile, said that while Israel would not intervene in the Syrian crisis, it would respond to any violation of its security interests.

"Across the border a bloody civil war has been taking place for the past two years with tens of thousands dead, but we will not intervene as long as the fighting does not affect our security interests," Ya'alon said. "When it does, whether the sporadic shooting is intentional or not, we will respond, just as we did last week." 

Ya'alon also that Israel was determined to prevent the transfer of arms from Syria to Hezbollah. "We have acted and will continue to act to thwart the transfer of weapons to the hands of irresponsible elements," he said.

The new defense minister hinted that Israel was behind an aerial attack two months ago that targeted a weapons convoy in Syria, possibly confirming foreign media reports.

Former Defense Minister Ehud Barak had also previously hinted that Israel was responsible for the attack, telling the media at a European security conference that "what happened in Syria proves that when we say something we mean it – we will not allow advance weapon system to be transferred to Lebanon."

Far away from the border with Israel, fierce battles raged Tuesday between Syrian rebels and government forces across eastern districts of Damascus, activists said.

Five shells fell on the north-eastern neighborhood of Barzeh, inflicting casualties, the pro-government al-Dunia television station also reported without giving details.

The Syrian Observatory for Human Rights, a Britain-based opposition organization, said at least four people from the same family were killed in the shelling on Barzeh, where it said there was heavy fighting.

Clashes and shelling were also taking place in parts of the Jobar district near al-Abbasiyeen square on the eastern fringe of central Damascus, the opposition group said.

Fighting has increased in southern and eastern Damascus since late March, and rebel mortar attacks on government-held areas have intensified. Last week, rebels warned civilians to evacuate areas near government buildings and security installations.