A rocket fired from Gaza struck a residential home in southern Israel early on Wednesday and the Israeli military began attacking militant sites in Gaza in response after days of rising tensions.

The Magen David Adom medical service said a woman and her three children, whose home in Beersheba was struck, were being treated for shock after they fled to their shelter upon being awaken by warning sirens shortly before 4 am. Her swift response likely saved their lives, as the home was destroyed and debris was scattered throughout the neighbourhood.

The medical service said two other Beersheba residents were injured during the panic to seek cover.

The military said another rocket from Gaza landed in the sea, just off the coast of one of the larger cities in central Israel. No injuries were reported.

Following the attacks, schools in Beersheba were closed and Israel’s military chief was cutting short his visit to the US to come back and manage the crisis.

As a first response, Israeli military jets pounded Hamas targets across the Gaza Strip. The Gaza health ministry said a 25-year-old militant was killed inside one of the posts targeted. Three other people were wounded.

The rocket attack on Beersheba was the first in months and the first that hit an Israeli home there since the 2014 summer war between Israel and Gaza’s militant Hamas rulers.

Beersheba, which is some 50 km from Gaza, is the biggest city in southern Israel, with a population of around 200,000.

Israel and Hamas have fought three wars over the past decade and fighting has flared up on several occasions recently, though neither side appears to be interested in another full-blown war. Egypt has been trying to mediate a long-term cease-fire to stave off another confrontation.

In a rare move, seemingly aimed at easing the tensions, the so-called “joint coordination room of resistance factions” that includes Hamas, the Islamic Jihad and other groups issued a statement distancing themselves from the rocket fire.

“We reject all irresponsible attempts that try to change the direction and sabotage the Egyptian efforts, including the overnight firing of the rocket,” they said. “At the same time, we emphasise we are ready to confront the Israeli aggression”.

The head of Egyptian military intelligence, Abbas Kamel, is scheduled to visit Gaza this week to renew high-level cease-fire talks.

The rocket attack came a day after Israeli defence minister Avigdor Lieberman said the time had come to deliver a “heavy blow” to Hamas after weeks of escalating violence along the border. Lieberman announced on Wednesday that all crossings into Gaza were being shut in response to the attack and the fishing zone around Gaza was being limited.

Hamas has held weekly border protests for the past six months, aimed in part at easing a crippling Israeli-Egyptian blockade that was put in place after the Islamic militant group violently seized power in 2007. The blockade has restricted Hamas’s ability to govern and made life extremely difficult for Gaza’s 2 million residents.