JENIN (Ma'an) -- Imprisoned Islamic Jihad leader Khader Adnan entered the 37th day of a hunger strike on Monday, and vowed to continue until his release.

Adnan was detained by Israeli forces on Dec. 17 from his Jenin home. He has been on a hunger strike in al-Ramleh jail since his arrest to protest against his treatment by prison authorities.

His lawyer said he had refused food, salt and medical checks, but vowed he had the strength to continue his hunger strike, asking his family not to worry.

The Islamic Jihad leader said that after being arrested an Israeli interrogator dragged him to the floor by his beard. The Israeli officer then used Adnan's beard to polish his shoes, Adnan told a lawyer from the prisoners society.

On Friday, the Islamic Jihad movement organized a solidarity protest, calling on people to support Adnan until Israel decides to release him.

Facebook, meanwhile, has blocked a page expressing solidarity with the detainee, according to Internet researcher Ali Saed. He suspected Israeli activists were behind the decision which he called unfair.

Facebook has blocked pages in the past which expressed solidarity with the Palestinian cause.