Sporadic rocket fire into southern Israel continued Thursday, March 15 after two overnight airstrikes on the Gaza Strip, the Israeli military said.

As M&C reported citing DPA, the airstrikes - south-east of Gaza City and east of Khan Younis in the south of the coastal enclave - were in retaliation to the firing of a Russian-type Grad missile at the southern Israeli city of Beersheba Wednesday night.

A missile battery of Israel's Iron Dome defence system shot it down, as well as a second Grad launched towards Beersheba the same day. Another rocket landed in a field near the southern Israeli town of Netivot, east of Gaza City, earlier Wednesday.

No injuries were reported in the overnight airstrikes. An Israeli military statement said the targets were a rocket launching site in farmland in northern Gaza and a tunnel dug by militants in the south.

Early Tuesday, a fragile informal truce took effect between Israel and two Palestinian militant factions, the Islamic Jihad and the Popular Resistance Committees (PRC).

The factions had fired more than 200 rockets at southern Israel since Friday, to avenge the killing that day of PRC secretary general Zohair al-Qaisi by Israeli forces.

Israel said al-Qaisi had been planning a cross-border attack against it from the Egyptian Sinai peninsula, and responded to the subsequent barrage of Palestinian rockets with airstrikes that killed 20 militants and four civilians.

A 15-year-old boy was killed in an explosion north of Gaza City Monday, which Palestinians said was caused by a missile fired by an Israeli drone. Israel suggested it was caused by the malfunctioning of a rocket launcher a group of children had been playing with.

Tit-for-tat violence has scaled down since the truce took effect, but sporadic rocket fire and Israeli retaliatory airstrikes have continued.