The US military dropped more than 45 tons of ammunition in north - eastern Syria to rebels. US-led coalition forces parachuted in ammunition to rebels in Syria, stepping up their support for groups battling jihadists as regime troops fought their fiercest clashes in weeks, aided by Russian air strikes. Moscow entered Syria's multi-faceted civil war last month, when it began air strikes against Islamic State jihadists and other "terrorists" fighting against the regime of its ally President Bashar al-Assad. Washington and Europe, however, accuse Moscow of targeting "moderate" groups that oppose the Syrian leader, rather than IS, and say ousting Assad is key to ending the bloody four-year conflict.