The latest strikes came on the third day of a US-led air campaign aimed at rolling back ISIS in Syria, and appeared to be aimed at one of the militants main revenue streams. The US has been conducting air raids against the group in neighbouring Iraq for more than a month.
The ISIS is believed to control 11 oil fields in Iraq and Syria, and to earn more than $3 million a day from oil smuggling, theft and extortion. Those funds have supported its rapid advance across much of Syria and Iraq, where it has carved out a self-styled caliphate straddling the border, imposed a harsh version of Islamic law and massacred its opponents.
At least four oil installations and three oil fields were hit around the town of Mayadeen in the eastern province of Deir el-Zour, according to the Britain-based Syrian Observatory for Human Rights and two local activist groups. A third activist group loyal to the militants confirmed the reports. It wasnt immediately clear how important the refineries and fields were.
At least 14 militants were killed, said the Observatory. Another five people in the northeastern Hassakeh province were also killed, the Observatory said.
The planes came with a terrifying sound and red lights before the explosions, one activist wrote, documenting each explosion.
The militants meanwhile freed at least 150 people from a prison in their de facto capital of Raqqa in northeastern Syria, fearing more strikes, according to activists there.
Other strikes hit checkpoints, compounds, training grounds and vehicles of the ISIS throughout the territory they hold along the Euphrates River in northern and eastern Syria, with strikes hitting near the Turkish and Iraqi borders.
The raids targeted Syrian military bases seized by the ISIS, including the Brigade 93 and Tabqa bases. They also hit a building used as an Islamic court and a cultural centre in the town of Mayadeen, the activists reported.
Elsewhere in Syria, forces loyal to President Assad wrested back a rebel-held industrial area near Damascus after months of clashes, according to the Observatory and pro-Assad Lebanese media.
The pro-government forces seized the Adra industrial zone after rebels accused them of using chemical explosives Wednesday. Footage of the wounded from the incident, in which six people were killed, showed men jerking uncontrollably and struggling to breathe before their bodies went limp. The footage, posted on social networks, appeared genuine and consistent with AP reporting of the event depicted.