The Minnesota Vikings announced Sunday the unexpected death of offensive line coach Tony Sparano.

Sparano, 56, served as the Vikings offensive line coach since 2016.

Over nearly two decades coaching in the NFL, Sparano worked with nine different teams, serving as the head coach with the Miami Dolphins from 2008-2011 and the interim head coach of the Oakland Raiders in 2014.

“Our hearts go out to Jeanette and the entire Sparano family as we all mourn the loss of Tony,” Vikings owners Mark and Zygi Wilf said in a statement. “Tony was a passionate and driven individual who cared deeply about his family, and especially enjoyed spending time with his grandchildren. Tony's presence within the Vikings organization will be deeply missed. We are only thinking of Tony’s family during this incredibly difficult time. We ask that the entire NFL and Vikings family keep the Sparanos in their thoughts.”

Sparano’s cause of death was not released.

In a statement Sunday, the Vikings said the team would provide more details about Sparano’s death when appropriate.