DHAKA: Islamic State militants have seized the last Syrian government-controlled border crossing between Syria and Iraq, a Syrian activist group says, reports BBC.
Government forces withdrew from al-Tanf - known as al-Waleed in Iraq - crossing as IS advanced, the Syrian Observatory for Human Rights (SOHR) said.
The loss of al-Tanf to IS follows the group's takeover of the ancient city of Palmyra on Thursday.
The US says that fighting the militants will be a "difficult challenge".
Islamic State now controls "more than 95,000 sq km (36,679 sq miles)" of Syria, which is 50% of the country's entire territory, the SOHR said.
The militants dominate the provinces of Deir Ezzor and Raqqa and have a strong presence in Hasakeh, Aleppo, Homs and Hama.
However, there are large areas under IS control in the east that are not very significant strategically.
BDST: 1218 HRS, MAY 22, 2015
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