"We thank Amir for his contributions to our club over the last three years," said Red Bulls sporting director Denis Hamlett. "Amir has continued to grow as a player and person since he joined us as a 20-year-old, and we wish him the best of luck in Europe."
Hamlett added: "The allocation money we receive as funds from this transfer will be invested back into improving our roster in this transfer window."
Murillo, 23, spent the past three years with New York after moving over from San Francisco FC in February of 2017.
"This is a great opportunity for Amir," said Red Bulls coach Chris Armas. "On behalf of the coaching staff I'd like to thank Amir for his commitment to the team during his time here. We wish him all the best and we will be rooting for him."
Murillo made 80 appearances in all competitions for the Red Bulls, scoring four goals and providing eight assists.
He has received 35 caps for his country since debuting in March of 2016, scoring twice.
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