"Security forces in Mosul are training an additional 500 police with the help of Spanish instructors," the Central Command said in a Twitter post.
Spain has sent about 300 military personnel to Iraq and leads the coalition efforts to train Iraqi Security Forces, including special forces and conventional warfare training.
More than 900 Spanish military personnel have served in Iraq since Operation Inherent Resolve began in 2014.
In July, Spanish Defense Minister Pedro Morenes said the coalition had asked Madrid to increase its training of Iraqi troops.
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