Buffalo Bills super-fan Pancho Billa has died.

Ezra Castro, a native of Texas, had gone through cancer treatments since 2017. Ever since, fans, players, Bills management and the franchise’s owners all rallied to his cause and his masked persona.

On Tuesday morning, after weeks of updates that Castro’s health was declining, it was announced on his Twitter account that Pancho Billa had died.

Kim Pegula released a statement on Castro’s death:

Others have also reacted to the death of the Bills super-fan:

Dozens of fans have also chosen to honor Castro by donating to Roswell Park in his name. You can make a donation to Roswell Park here.