JERUSALEM -- Israel's military said it downed a drone along its southern coastline on Monday, the first time it encountered such a weapon since its campaign against the Gaza Strip militants began last week.
The drone came from Gaza and was shot down near the southern city of Ashdod, the military said. It did not say what the drone was carrying.
Hamas tweeted Monday that it had "deployed a number of pilotless drones into Israel."
Israeli TV was reporting there could have been at least a second drone fired toward the Jewish state.
Since the latest bout of fighting began last Tuesday, militants have fired nearly 1,000 rockets at Israel, causing some injuries and damage to property, but no fatalities among Israelis. By contrast, say Palestinian officials, 172 Palestinians have died as a result of Israel's air attacks.
But the use of unmanned aircraft with an offensive capacity could potentially inflict significant casualties - something the rockets from Gaza have failed to do, largely because of the success of the military's 'Iron Dome' air defense system in shooting them down.
Israel began airstrikes Tuesday against militants in the Hamas-controlled Gaza Strip in what it says was a response to heavy rocket fire out of the densely populated territory. The military says it has launched more than 1,300 airstrikes since then, while Palestinian militants have launched nearly 1,000 rockets at Israel.
The Palestinian Health Ministry in Gaza says 172 people have been killed, including dozens of civilians.
Though there have been no Israeli fatalities, several people have been wounded, including a teenage boy who was seriously injured by rocket shrapnel on Sunday.
The military said Monday's drone was launched from Gaza and was shot down in mid-flight by a Patriot surface-to-air missile near Ashdod.
Israeli Prime Minister Benjamin Netanyahu said Sunday that the current Israeli operation could last for "a long time" and that the military was prepared "for all possibilities." That includes a wide-ranging Gaza ground operation, which would likely cause heavy casualties in the coastal strip. Thousands of Israeli troops have massed along the border in recent days.
The fighting showed no signs of slowing, despite international calls for a cease-fire and growing concerns about the mounting civilian death toll in Gaza.
Netanyahu, in particular, is coming under increasing international pressure to end the Israeli operation soon.
Hamas has sent signals it may be ready to consider a cease-fire but appears to be waiting for some tangible military or diplomatic achievement before moving ahead on that front. For his part, Netanyahu wants to show the Israeli public that he has succeeded in significantly degrading Hamas's ability to strike at its Israeli targets before moving ahead diplomatically.
Israel says its punishing air assault on Hamas militants, their property and their weaponry has delivered a devastating blow to the Islamic militant group. Yet rocket fire at Israel has continued almost unabated.
The military says that, due to years of generous Iranian shipments, thousands of rockets remain in Gaza, and there is no quick way to eliminate the threat.
It says its goal is to inflict so much pain on Hamas that it will be deterred from attacking Israel again -- just like Hezbollah guerrillas in Lebanon have largely remained on the sidelines for the past eight years.
The military also says it wants to punish Hamas for the violence. But both goals are hard to quantify in the short term. A similar offensive in November 2012 was also deemed a military success, though it left Israel vulnerable to rocket fire. Israel also launched a large offensive in late 2008 that delivered a tenuous cease-fire.
"There is no knockout, it is more complicated," said a senior military official involved in the fighting, who spoke on condition of anonymity under military guidelines. But, he added, "if there is a map of pain that the enemy sees, it will have to think about things."
The rocket threat has been in the making for well over a decade. In the early 2000s, Hamas began firing rudimentary, homegrown rockets that were inaccurate, flew short distances and carried a tiny payload.
Today, the army says the group has an arsenal of some 10,000 rockets, including longer-range, foreign-made weapons capable of reaching virtually anywhere in Israel. The current round of fighting has seen air-raid sirens sound in Jerusalem, Tel Aviv and Haifa, Israel's three-largest cities.
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