A video of the attack, which occurred on a brown rocky hillside, was posted on YouTube and sent to the media.

It showed a masked man with a rock in his left hand pushing Ascherman down the hill.

The man then drew a knife out of his back right pocket and pulled it on Ascherman as he forced him backwards down the hill a bit before running after a Belgian journalist.

When Ascherman went to help the Belgian journalist, the masked man turned on him again and the journalist was able to get away safely.

The two men continued to tussle, with the masked man kicking Ascherman several times and swinging the knife, without actually stabbing him.

Ascherman at one point was able to grab hold of his leg as the masked man swung and in return, the man briefly put his arm around Ascherman’s neck in a headlock, before running away up the hill.

Ascherman told The Jerusalem Post that he had arrived with a group of left-wing activists to help Palestinians harvest olives down the hill from an outpost that is close to the settlement of Itamar, which is located in the Samaria region of the West Bank.

The olive harvest was coordinated with security forces, who asked the farmers to stop work as of 12:30 p.m., he said.

Ascherman charged that after the security forces left, people whom he presumed to be settlers entered the Palestinian groves. They stole olives and equipment as well as lit some of the trees on fire.

He went up to the grove with a Belgian journalist to see if they could help put out the fire, when the masked man attacked them, Ascherman said.

“He pulled a knife on me and I started to move backward on a steep hill. I lost my footing a bit. At that point I tried to grab his arm and his left. He made a motion as if he was going to stab me, but then he ran away.”

A Judea and Samaria spokesman said that the incident happened after an altercation between left and right wing activists. The National Crimes Unit has opened an investigation into the matter, he said.

“We take violent incidents like this very seriously and have zero tolerance for law breakers,” the spokesman said.

An earlier statement, however, referred to Ascherman’s group as “anarchists” and “provocateurs” whose actions led to the attack.

Ascherman said that such accusations were insulting.