Occupied Jerusalem:  Israel bombed targets in the Gaza Strip early on Friday, hours after two rockets were launched at Tel Aviv in the first such attack since a 2014 war.

After the overnight exchanges, sirens sounded again in Israeli border towns after dawn. The Israeli military alleged two more missile launches from the Gaza Strip toward Israel, but said both were intercepted by Israel's Iron Dome defence system.

Palestinian news media reported strikes throughout Gaza, from Rafah in the south to the north of the densely populated coastal strip that is home to two million Palestinians.

Most of the Israeli strikes were reported to have targeted facilities used by Hamas's security forces. The buildings had been evacuated as a precaution, as the group had expected an Israeli response.

Health ministry officials in Gaza said two people, a man and a woman, were wounded when their house was damaged in Rafah in the early morning.

Witnesses said powerful explosions from the air strikes rocked buildings in Gaza and lit the skies over targeted sites.

On Thursday night, the sirens howled farther north, in Tel Aviv, Israel's commercial capital, set off by what the military said were two incoming, longer-range rockets from Gaza.

That salvo caused no casualties or damage, missing built-up areas. But it rattled Israeli nerves ahead of an April 9 election in which Prime Minister Benjamin Netanyahu is seeking a fifth term on the strength of his national security credentials.

Explosions were heard in Tel Aviv and witnesses said interceptor missiles had and detonated - although the military said no rockets were shot down.

It was the first such attack on the city since the 2014 Gaza war between Hamas and Israel. There have been several smaller rounds of fighting since, reined in by Egyptian and U.N. mediations.

Hamas denied involvement, saying the launches took place as its leaders met Egyptian delegates about efforts to secure a long-term ceasefire with Israel.