MUSITPINAR, Turkey (AP) — Syrian activists say a U.S.-led coalition airstrike in an eastern Syrian stronghold of the Islamic State group killed at least eight people.

Deir el-Zour Free Radio says the strike targeted a gas distribution station and set off a series of secondary explosions. It says those killed were mostly fuel tanker drivers. The activists say other airstrikes targeted oil wells in the oil-rich Deir el-Zour province.

The U.S.-led coalition has aggressively targeted IS-held oil facilities in Syria, which provide a key source of income for the militants. But such strikes also endanger civilians.

Recent coalition airstrikes have focused around the Syrian border town of Kobani, which militants have been trying to seize since mid-September. Gun and mortar fire is being heard from the town today, while an airstrike sent a huge plume of black smoke into the sky. A senior town official says the airstrikes have helped halt the advance of the militants, though Kurdish fighters defending Kobani still need more weapons and ammunition to save the town.

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