Three Palestinians were killed and two others were seriously wounded in an Israeli security forces joint raid on occupied West Bank's Nablus on Thursday.

"Medical teams recovered the bodies of three Palestinians in a house besieged by Israeli forces in the Old City of Nablus," the official Palestinian TV reported.

"Two of the martyrs have completely distorted features due to the intensity of the shooting, which makes it difficult to identify them," the Palestinian Health Ministry said in a statement confirming the deaths.

Meanwhile, the Palestine Red Crescent Society said its "crews dealt with two serious injuries caused by live bullets during clashes that erupted between dozens of Palestinians and the Israeli army in Nablus.​​​​​"

The Directorate of Education in Nablus announced the postponement of school hours until the end of the military operation.

An Agence France-Presse (AFP) correspondent reported that gunfire erupted near the Old City around 7 a.m. (4 a.m. GMT) as dozens of Israeli army vehicles swooped in from multiple directions.

In a statement, the Palestinian armed group Hamas described the killing of the three Palestinians as an "assassination" of the "heroes of resistance in the city of Nablus."

Israel, in its version of the events, blamed the three Palestinians for the killing of a British-Israeli woman and her two daughters last month.

It accused the three dead as the "murderers of Leah, Maia and Rina Dee" who died after the April 7 attack on their vehicle near Hamra in the Jordan Valley, Shin Bet said, using the women's Hebrew names.

In a separate statement, the Israeli army named the two alleged Hamas operatives as Kassan Katnani and Maed Mitsri, and the alleged accomplice as Ibrahim Hura.

The raid came just days after violence flared along the Gaza border following the death of a Palestinian hunger striker in Israeli custody Tuesday.

Palestinian armed groups in Gaza exchanged rocket fires with Israel following the death of Khader Adnan, 45, a leading figure in Islamic Jihad in the occupied West Bank, who died in prison following an 87-day hunger strike.

Tensions have been running high across the occupied West Bank in recent months amid regular Israeli raids into Palestinian towns.

The latest deadly raid brings to 105 the number of Palestinians killed in the Israeli-Palestinian conflict so far this year.

Nineteen Israelis, one Ukrainian and one Italian have also been killed over the same period, according to an AFP count based on official sources from the two sides.