U.S. airstrikes destroyed around 280 of ISIS' oil tanker trucks along the Syria-Iraq border on Monday, U.S. officials told NBC News.
The vehicles were targeted at a "fuel collection point" in the Syrian city of Deir ez-Zor.
Before the strike, the planes dropped leaflets warning the drivers to "run immediately or you will be killed," according to the officials, who spoke on condition of anonymity.
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Airstrikes against ISIS have intensified after the terror group claiming responsibility for the massacre in Paris as well as blowing up Russia's Metrojet passenger jet.