At least four Palestinians have been killed during raids by the Israeli army in the West Bank, the Palestinian health ministry says.
Heavy fighting is said to be continuing near the city of Jenin.
Israeli Prime Minister Naftali Bennett said Israeli forces had mounted an operation against Hamas militants about to carry out attacks.
Israeli officials did not comment on the casualties but local media said at least four Palestinians were killed.
The Palestinian sources said one person had been killed in Burqin near Jenin and another three in Biddu near Jerusalem.
Correspondents say there has long been concern in Israel that Hamas, which runs Gaza, could also challenge its rival the Palestinian Authority in the West Bank.
Last week in Jenin, Israel recaptured the last two of six fugitive Palestinian militants, who had escaped from a maximum security prison two weeks earlier.
And in August four Palestinians were killed in an Israeli raid to arrest a suspect in the West Bank.
Weeks before that, two Palestinian intelligence officers and a Palestinian suspected by Israel of carrying out attacks were killed during an undercover raid in Jenin.
At least 256 people were killed in an 11-day conflict in May between Israel and Palestinian militant groups in Gaza, according to the UN, and 13 people were killed in Israel.- BBC