Former Barcelona president JoanLaporta called Castel the club's greatest ever signing, while current Barca playmaker Xavi is among his legion of loyal fans.
JoanLaporta, president of European champions Barcelona -- Espanyol's city rivals -- said on their official Web site: ""We are very shocked by this tragic event.
The alleged activities took place under the presidency of JoanLaporta, who was at the helm from 2003-2010, one of the most successful spells for the famous Spanish club.
New Barcelona president JoanLaporta was under pressure to bring in a new manager and players after being outmanoeuvred by rivals Real Madrid for the signing of Manchester United's David Beckham.