Israel has started moving troop reinforcements to its border with the Gaza Strip, its military says, raising the possibility of an expanded operation in the Palestinian territory in response to intensifying rocket fire.

Thursday’s movement of tanks and artillery forces came after 11 Palestinians were wounded in Israeli air raids on Gaza, as Palestinians prepared for the funeral of a teenager who was killed in occupied East Jerusalem.

The Gaza raids began as residents were preparing their pre-dawn Ramadan meal, known as Sohour, on Thursday.

“Eleven people were wounded during the night, including one who is in serious condition,” a spokesman for the Gaza health authority said, adding seven were hurt in Beit Lahiya in the north and four in Gaza City.

The Israeli military said the air force struck 15 “terror sites” in Gaza. “The targets included weapons manufacturing sites as well as training facilities,” a military spokesman said.

The raids came after at least 15 rockets struck southern Israel, two of which were intercepted by Israel’s anti-missile system, the army said.

The rockets struck two houses in the southern border town of Sderot. Police said that one of the rockets caused a power cut. The army reported no injuries.

Israel’s last major operation in Gaza, a territory controlled by the Palestinian group Hamas, took place in late 2012.

‘Revenge’ attack

The tensions have heightened following the abduction and killing of three Israeli teens in the West Bank. Israel has accused Hamas of being behind the deaths, and arrested around 600 Hamas operatives in the West Bank as part of a broad manhunt in the largest ground operation in the West Bank in nearly a decade.

The Palestinians have meanwhile accused Israeli extremists of abducting and killing a teenage boy in east Jerusalem in a revenge attack, and stone-throwing youths clashed with Israeli police throughout the day on Wednesday.

The weeks since the Israeli teens disappeared have seen Palestinians in Gaza fire scores of rockets at Israel, which has responded with airstrikes against alleged militant targets.

Two Palestinian fighters were killed in an airstrike last week, and a young Palestinian girl was killed by an errant rocket attack. There have been no serious casualties on the Israeli side.

The armed wing of the Democratic Front for the Liberation of Palestine and the Al-Aqsa Martyr Brigades said in a statement that had they fired rockets.

They said they were “in response to the ongoing Israeli escalation against our people in Gaza and West Bank” – a reference to clashes in East Jerusalem after the murder of 17-year-old Mohammed Abu Khudair early on Wednesday.

According to figures from Dr Amin Abu Ghazali, the head of field operations for the Red Crescent in East Jerusalem, 232 people were wounded during the clashes, 178 of them in Shuafat alone.

The Palestinian president, Mahmoud Abbas, said it was clear that Khdair was killed by Jewish settlers and called on Israel to bring the killers to justice.

An investigation into the disappearance and murder of the teenager was launched by Israeli police after the prime minister, Benjamin Netanyahu, demanded a swift probe of what he called a “reprehensible murder”.

Khdair’s family said he was abducted on Wednesday shortly before a charred body was found in a Jerusalem forest. Police were still working to identify the body on Thursday.

“The investigation is continuing in order to determine whether this was criminal or nationalistic,” police spokesman Micky Rosenfeld said. Al Jazeera