JERUSALEM • Israeli forces on Wednesday stormed into a major Palestinian city in the occupied West Bank for a rare daylight arrest raid, triggering a gunbattle that killed at least 10 Palestinians and wounded scores.

It was one of the bloodiest battles in nearly a year of fighting in the West Bank and east Jerusalem and raised the likelihood of further bloodshed. Israeli police said they were on heightened alert, while the Hamas militant group in Gaza said its patience was “running out.” Islamic Jihad, another militant group, vowed to retaliate.

Among the dead were two Palestinian men, ages 72 and 61, and a 16-year-old boy, according to health officials.

The four-hour offensive left a broad swath of damage in a centuries-old marketplace in Nablus. In one emotional scene, an overwhelmed medic pronounced a man dead, only to notice the lifeless patient was his father. Israel has been carrying out stepped-up arrest raids of wanted militants in the West Bank since a series of deadly Palestinian attacks in Israel last spring.

Israeli officials liken these operations to “mowing the lawn,” saying they are necessary to prevent a difficult situation from turning worse. But the raids have shown few signs of slowing the violence

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Smoke from fires Wednesday fills the air as Palestinians clash with Israeli forces in the West Bank city of Nablus.

The Associated Press