(Bloomberg) -- A surprise multifront attack on Israel by the Palestinian group Hamas will likely lead to a massive military retaliation on Gaza and possibly to a wider conflagration with repercussions beyond the Middle East.

The flare-up — involving infiltrations, capture of soldiers and civilians, and thousands of rockets — comes at a time of enormous diplomatic sensitivity and a moment of weakness for Israel that analysts have been warning its enemies might seek to exploit.

The country is in negotiations with the US and Saudi Arabia on a complex three-way deal in which Washington would offer security guarantees to Riyadh. The Saudis, for their part, would normalize relations with Israel. Israel has also been talking with Turkey and others about gas exports to Europe along with corridors for trade from Asia.

Internally, Israel has been embroiled in political turmoil that left it vulnerable. Last April, the nation found itself briefly engaged on three fronts simultaneously — Gaza, Lebanon and Syria — after rocket fire came from all three. Part of the trigger was that Israeli Jews entered the grounds of the al Aqsa mosque compound in Jerusalem. This past week, that too occurred.

“I can’t exclude a multi arena war that will cause a very very severe threat to the state of Israel,” Giora Eiland, a former national security adviser in Israel, said in a briefing with journalists. He added, though, that Israel prefers to fight one enemy at a time and would not be quick to open another front.

Israel Latest: PM Says Nation Is at War After Deadly Incursion

Israeli officials have been saying for months that Palestinian militant groups, guided and funded by Iran, were preparing for violence and that Israel was ready to strike back. That said, Saturday’s attack on the Sabbath and Jewish holiday caught the country distinctly by surprise, adding to a sense of injury that could feed its response.

Nation at War