AMMAN (Reuters) - Islamic State bombers have blown up about a dozen explosive-packed trucks at Syrian army checkpoints around the government-held northeastern city of Hasaka city over the past five days, the city governor said on Thursday.
Government troops and militias have been battling to repel Islamic State attacks to the south of Hasaka, which is close to the Iraqi border.
"More than thirteen explosive-laden vehicles have attacked army checkpoints and sowed terror and fear among citizens," City Governor Mohammad Zaal al Ali told state television by telephone from inside the city.
Despite the attacks, the militants has been repelled and the army was manning new checkpoints across Hasaka.
Rami Abdulrahrman of the Syrian Observatory for Human Rights monitor said on Thursday that Islamic State fighters had moved to within 500 m (0.3 miles) of the city's southern entrance.
Islamic State has been stepping up lightning attacks on the southern edge of the ethnically mixed city, which is divided into zones run separately by the government of President Bashar al-Assad and a Kurdish administration.
The Kurds have a well-organized militia which receives air support from a U.S.-led alliance and has been pushing back the jihadists further north west along the Turkish border.
(Reporting by Suleiman Al-Khalidi; Editing by Angus MacSwan)