TEHRAN Four Palestinian prisoners of war, captured during the 1980-88 Iraqi imposed war, have been released following a request by the visiting leader of the Islamic Resistance Movement of Palestine, Hamas, Sheikh Ahmed Yassin. The four Palestinians met Sheikh Yassin on Monday. The Hamas leader thanked the Leader of the Islamic Revolution Ayatollah Seyed Ali Khamenei, President Mohammad Khatami and senior officials of Iran for securing release of the Palestinian POWs. One of those released expressed his deep gratitude to the Iranian government and the nation for their warm hospitality during the years of captivity.