BEIRUT -- The Israeli military launched small ground raids against Hezbollah and sealed off communities along its northern border as signals grew that more forces could soon be sent across the border to fight the Iran-backed militants.

U.S. State Department spokesman Matthew Miller said Monday Israel informed the U.S. about the raids, which he said were described as “limited operations."

A Western diplomat told the AP a wider ground operation was “imminent.â€

Israeli artillery pounded southern Lebanon, though it was not clear if Israel had made a final decision on sending in significant ground forces.

The Israeli military did not comment on its plans.

This is a developing news story from The Associated Press. Check back for updates.

Original copy from Reuters follows.

Hezbollah's deputy leader Naim Qassem, in his first public address since Israel assassinated the group's chief Hassan Nasrallah last week, said the movement is ready to confront any Israeli ground invasion of Lebanon.

Israel will not achieve its goals, he said.

"We will face any possibility and we are ready if the Israelis decide to enter by land and the resistance forces are ready for a ground engagement," he said.

Israeli forces have dealt multiple blows to Hezbollah in a two-week wave of attacks on targets in Lebanon that has eliminated several commanders. The possibility that Israel's next move might be to send ground troops and tanks over the border is on many minds.

In other developments, the Palestinian militant group Hamas said an Israeli airstrike killed its leader in Lebanon in the city of Tyre on Monday, and another Palestinian organization said three of its leaders died in a strike in central Beirut - the first such hit inside the capital's limits.

The killings were the latest in a wave of intensified Israeli attacks on militant targets in Lebanon, part of a conflict also stretching from the Palestinian territories of Gaza and the occupied West Bank, to Yemen, and within Israel itself.

Hamas said its leader in Lebanon, Fateh Sherif Abu el-Amin was killed along with his wife, son and daughter, in a strike that targeted their house in a refugee camp in the southern city of Tyre in the early hours of Monday.

Another group, the Popular Front for the Liberation of Palestine (PFLP), said three of its leaders were killed in a strike that targeted Beirut's Kola district.

This was the first time Israel had struck Beirut beyond its southern suburbs in a campaign which culminated in the assassination of Hezbollah's veteran leader Hassan Nasrallah last week in a succession of heavy air strikes.

The strike against the PFLP hit the upper floor of an apartment building, Reuters witnesses said. There was no immediate comment from the Israeli military.

The latest attacks indicated Israel has no intention of slowing down its offensive on multiple fronts even after eliminating Nasrallah, who was Iran's most powerful ally in its "Axis of Resistance" against Israeli and U.S. influence in the region.

Israel's intensified attacks against the Iran-backed Hezbollah in Lebanon and Houthi forces in Yemen have prompted fears that Middle East fighting could spin out of control and draw in Iran and the United States, Israel's main ally.

Iranian Foreign Ministry spokesperson Nasser Kanaani said Tehran would not leave any of Israel's "criminal acts" go unanswered. He was referring to the killing of Nasrallah and an Iranian Guard deputy commander, Brigadier General Abbas Nilforoushan, who died in the same strikes on Friday.

Lebanon's Health Ministry says more than 1,000 Lebanese have been killed and 6,000 wounded in the past two weeks, without specifying how many were civilians. One million people - a fifth of the population - have fled their homes, the government says.

The escalation has put Beirut on edge, with Lebanese fearful that Israel will expand its military campaign.

"There is nothing else to say or add, except God save Lebanon," Beirut resident Nawel said. "What will happen to me is the same as what can happen to anyone."

(Reporting by Maya Gebily, Laila Bassam, Ali Sawafta, Yomna Ehab, Mohammed Al Gebaly and Emma Farge and Elwely Elwelly; Writing by Andy Sullivan and Michael Georgy; Editing by Lincoln Feast and Angus MacSwan)