FIFA says it has given Caribbean soccer leaders 48 hours to explain their part in a Trinidad meeting where Mohamed bin Hammam allegedly offered them bribes or face life bans from the sport.
FIFA says "any person who has relevant information" but doesn't come forward "will be subject to the full range of sanctions."
FIFA banned bin Hammam for life on Saturday after ruling he offered $40,000 cash bribes to Caribbean officials to back his later-abandoned presidential bid.
FIFA says it wrote Monday to all Caribbean Football Union members asking "their presidents and any of their members ... (for) knowledge of anything that transpired" in Trinidad.
The deadline for evidence to be submitted is Wednesday.