JERUSALEM/GAZA (Reuters) - Four rockets were fired at Israel from the Gaza Strip on Wednesday, the Israeli military said, and it responded with air strikes against facilities belonging to the enclave’s ruling Hamas militant group.

No casualties were reported on either side of the Israel-Gaza border.

Two of the projectiles launched from Gaza were shot down by Israel’s Iron Dome air defence system, the military said in a statement. Israel’s Channel 13 television said the other two struck uninhabited areas.

Sirens warning of rocket fire sounded in several Israeli communities near the Gaza frontier. Israel’s Magen David Adom ambulance service said no injuries or damage were reported in the first such attack in three weeks.

There was no immediate claim of responsibility from the Gaza Strip, which Israel keeps under blockade citing security concerns over Hamas, the dominant armed movement in the Palestinian territory.

The Israeli military said that in response to the rocket attack, its warplanes struck several “Hamas terror targets” in the northern Gaza Strip, including a weapons manufacturing facility and an armed compound.

Hamas’s armed wing usually evacuates its facilities in anticipation of Israeli retaliation after cross-border rocket strikes.

A statement by the Israeli military did not accuse Hamas of launching the rockets but said that it holds the group responsible “for all events transpiring in the Gaza Strip”.

Last month, a rocket was launched from the Gaza Strip at the southern Israeli city of Ashkelon as it hosted a rally with Prime Minister Benjamin Netanyahu, prompting him to seek shelter briefly before returning to the venue. No one was hurt.

But simmering tensions have mostly remained calm since a two-day surge of violence in November between Israel and the armed Gaza-based faction Islamic Jihad that left 34 Palestinians dead and dozens of Israelis injured.