Two Palestinians were killed in the city of Jenin, four others in a nearby village, and four more in a refugee camp near the town of Tubas, Red Crescent spokesman Ahmed Jibril told AFP.

He added that 15 others had been wounded.

The Israeli army said early Wednesday it was carrying out "a counterterrorism operation" in the cities of Jenin and Tulkarem in the northern West Bank.

Foreign Minister Israel Katz said on X that the army was "operating in full force since last night" in refugee camps in the two cities "to dismantle Iranian-Islamic terror infrastructures established there."

He said Iran was "working to establish an eastern front against Israel" in the West Bank, "following the Gaza and Lebanon model, by funding and arming terrorists and smuggling advanced weapons from Jordan."

He added: "We must address this threat with the same determination used against terror infrastructures in Gaza including temporary evacuation of residents and any necessary measures. This is a war, and we must win it."

Violence in the West Bank has surged alongside the war in Gaza, with more than 650 Palestinians killed by Israeli troops and settlers since Hamas's October 7 attack, according to an AFP tally based on Palestinian health ministry figures.

At least 19 Israelis have been killed in Palestinian attacks during the same period, according to Israeli officials.

But while Israeli military operations have become a daily occurrence in the West Bank, occupied by Israel since 1967, it is rare for them to be carried out in multiple cities simultaneously.

In recent weeks Israeli operations in the West Bank have focused on the north of the territory, where armed groups fighting against Israel are particularly active.

The latest operation comes two days after Israel said it carried out an air strike on the West Bank that the Palestinian Authority reported killed five people.

The Israeli army confirmed the five deaths on Wednesday and said the strike hit a structure "used by the terrorists to conduct terrorist activity and harm [Israeli] soldiers operating in the area".

It identified one of the dead as Jibril Jasan Ismail Jibril, who was released in November as part of the only truce so far in the Gaza war.

Last week the army announced it had killed a senior Palestinian militant in Lebanon, accusing him of "directing attacks and smuggling weapons" to the West Bank and collaborating with Iranian forces.

Islamic Jihad, a Palestinian Islamist movement allied with Hamas which has a strong presence in the north of the West Bank, issued a statement early Wednesday denouncing an "open war" by Israel.

"With this aggression which aims to transfer the weight of the conflict to the occupied West Bank, the occupier wants to impose a new state of affairs on the ground to annex the West Bank," the statement said.

Hamas, whose popularity has soared in the West Bank since the start of the Gaza war, late Tuesday reiterated its call for Palestinians there to "rise up".

Its statement came in response to comments by far-right Israeli National Security Minister Itamar Ben Gvir, who this week he would build a synagogue at Jerusalem's flashpoint Al-Aqsa mosque compound if he could.

Ben Gvir, a settler himself, has openly called for the annexation of the West Bank.

Hamas's October 7 attack resulted in the deaths of 1,199 people, mostly civilians, according to an AFP tally based on official Israeli figures.

Israel's retaliatory military campaign since then has killed at least 40,534 people in Gaza, according to the territory's health ministry. The UN rights office says most of the dead are women and children.