At least nine Palestinians have been killed in Israeli raids and strikes in several towns in the north of the occupied West Bank.

The Israeli army is conducting one of its largest operations in the territory in years. The casualties are mounting from the operation, which has involved air raids and the use of military bulldozers to destroy civilian infrastructure.

Palestinian fighters have battled the military incursion, which began in the early hours of Wednesday.

The Israeli army said it was carrying out an “operation to thwart terrorism in Jenin and Tulkarem”, the raids coming two days after Israel said it carried out an air strike on the West Bank that the Palestinian Authority and health officials said killed five people.

Wednesday’s continuing operation was focused on three refugee camps in Jenin, Tulkarem and Tubas, with hundreds of ground troops also deployed.

At least 646 Palestinians, including 148 children, have been killed by Israeli soldiers and settlers in the occupied territory, according to Palestinian health officials. This includes at least 128 Palestinians killed by Israeli air attacks.