The 23-year-old Kinshasa-born player appeared to collapse with no players near him towards the end of the first half at White Hart Lane.
Several paramedics were seen attempting to revive the player before he was stretchered off the field after 41 minutes with the scores at 1-1.
Referee Howard Webb called the players off the field before an announcement shortly afterwards that the game had been abandoned.
Muamba was being taken to hospital while paramedics battled to revive him, ESPN television reported.
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