Witnesses and Palestinian health officials report that nine Palestinians, including an elderly man and several militants, were killed during an Israeli military raid in the occupied West Bank.
As troops raided the center of Nablus, explosions and gunfire could be heard, setting off armed encounters with armed assailants.
According to reports, two senior Palestinian militants were killed inside a house after being the target of heavy Israeli fire.
Earlier, the Israeli military confirmed that some of its soldiers were present in Nablus.
According to Palestinian health officials, a 72-year-old civilian was among those killed during the gunfights outside a besieged house.
In what is typically a bustling market area of the old city, video footage showed a body in the street next to bags of bread.
According to the health officials, more than 100 people were also shot, with six of them suffering serious injuries.
Israel has increased its intelligence gathering, arrest, and search operations in Nablus and the nearby Jenin over the past year in response to a string of deadly Palestinian attacks.
This latest one occurs despite reports this week of a deal the US helped to broker to reduce tensions.
At least 50 Palestinians, including militants and civilians, have died so far this year, whereas 11 people have died as a result of Palestinian attacks on Israelis.