Israel bombarded northern Gaza overnight in some of the heaviest shelling in weeks, panicking residents and flattening neighbourhoods in an area where the Israeli army had previously drawn down its troops, residents said on Tuesday.

Tanks made a new incursion east of Beit Hanoun on the northern edge of the Gaza Strip, though they did not penetrate far into the city, residents and Hamas media said. Gunfire reached some schools where displaced residents were sheltering.

In Israel, where government offices and businesses were shut to celebrate the Jewish Passover holiday, incoming rocket alerts sounded in southern border towns, although no casualties were reported.

The armed wing of the Islamic Jihad, a group allied to Hamas, claimed responsibility for the rocket attacks on Sderot and Nir Am, indicating fighters were still able to launch them almost 200 days into the war, which has flattened large swathes of the enclave and displaced almost all of its 2.3 million people.

Thick black smoke could be seen rising in northern Gaza from across the southern Israeli border. Shelling was intense east of Beit Hanoun and Jabalia and continued on Tuesday morning in areas such as Zeitoun, one of Gaza City’s oldest suburbs, with residents reporting at least 10 strikes in a matter of seconds along the main road.

Just west of Beit Hanoun in Beit Lahiya, medics and Hamas media said strikes had hit a mosque, injuring several people, and a crowd gathering on the coastal road to collect aid dropped from the air. Reuters could not immediately confirm those targets.

“It was one of those nights of horror that we have lived in at the start of the war. The bombing from tanks and planes didn’t stop,” said Um Mohammad, 53, a mother-of-six living 700 metres from Zeitoun.

“I had to gather with my children and my sisters who came to shelter with me in one place and pray for our lives as the house kept shaking,” she told Reuters via a chat app.

“I don’t know if we will make it alive before this war stops,” she added.

The Israeli army said rockets launched overnight into Israel had come from northern Gaza. It had struck rocket launchers and killed several militants.