Jordan has decided to renew a long dormant territorial dispute with Syria, and has issued Damascus with a formal demand to return territory illegaly seized in 1970. This has been confirmed by western intelligence sources. Jordanian officials have refused to comment. In September 1970 Syria attempted to invade Jordan and overthrow King Hussein, under the pretext of assisting the PLO uprising against the Jordanian government, in what became known as "Black September". Syrian president Nur'a din Attassi sent his 5th Armored division to invade Jordan and assist embattled PLO leader Arafat, who was besieged in Amman's refugee camps after having launched an unsuccessful uprising against the Hashemite dynasty. The invasion collapsed after Syrian air force commander Hafez Assad refused to allow his air force to provide air cover to the Syrian armor, out of fear Israel would send its air force to the aid of the Jordanian monarch. RJAF gave their ground forces effective air cover, almost annihilating the Syrian tanks in Jordan. In the wake of the debacle Assad succeeded in overthrowing Attassi in a bloodless coup, and assumed the presidency. However Syria retained in control of some 125 square kilometers (48 square miles) of Jordanian territory, which it holds to this day, and in which some 17,000 Syrians have been resettled. Prior to his death in 1999, King Hussein made several demands of Syria to return his land, but to no avail. Some 20,000 Syrian settlers now occupy the site under the protection of Syrian soldiers and police. The renewed Jordanian demand is based on the 1923 map, which delineated the border between what was then the British controlled East Palestine and French occupied Syria. The Jordanians claim the map clearly shows the disputed land belongs to Jordan.