Tulkarem, West Bank - An Israeli airstrike on the illegally occupied West Bank late Thursday killed at least 18 in the refugee camp of Tulkarem.

A source within the Palestinian security services told AFP that the air raid was the deadliest in the West Bank since 2000.

"Eighteen martyrs following the bombing of the Tulkarem camp by the occupation," the Palestinian health ministry said on its Telegram account.

The Israeli army confirmed the strike on the town in the northern West Bank, describing it as a joint operation carried out by the Shin Bet internal security service and the air force, according to a brief statement by the military.

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The Israeli military later said the strike had killed a Hamas leader in Tulkarem – Zahi Yaser Abd al-Razeq Oufi. It accused Oufi participating in attacks in the West Bank and said he was in the process of planning another assault.

Hamas condemned the air strike, calling it a "cruel attack" that would prove to be a "dangerous escalation."

Reached by telephone, camp official Faisal Salama told AFP that the attack had been carried out by an F-16 fighter jet.

Alaa Sroji, a social activist from the area, said the Israeli plane had "hit a cafeteria in a four-story building."

"There are many victims in the hospital," the resident added, saying the toll would likely rise.

The Palestinian movement Fatah, a Hamas rival based in the occupied West Bank, called for demonstrations on Friday to honor the "heroic martyrs" of Tulkarem.

Tulkarem was one of the towns and Palestinian refugee camps ravaged during a brutal week-long invasion in late August.

Israeli violence in the West Bank has surged alongside the destruction of Gaza. Troops or settlers have killed at least 701 Palestinians in the territory Israel is occupying in violation of international law.

At least 24 Israelis have been killed during the same period, Israeli officials say.