The West African Examinations Council (WAEC) has cancelled 151 certificates that had already been issued to both private and public examination candidates.
WAEC made the announcement during the 62nd meeting of its National Examinations Committee (NEC) held in Lagos on Tuesday.
The affected candidates were said to have engaged in examination malpractice.
The body equally retracted 29 other certificates belonging to both public and private candidates who, in search of restitution, returned their illegally obtained merits.
The cancelled certificates include two issued in 1989 and 1990 respectively, 13 each in 1990 and 2000, 12 certificates in 2003, 10 in 2006, eight in 1988, seven each in 2004, 2007 and 2010, five each in 1993, 1995, 2009, 2012 and 2013. Others are four in 1994 and 2008, three each in 1996 and 2011, two each in 1997 and 2005 as well as one each in 1989, 1990 and 1992
The highest number, 14, were issued in 2001 and 2002.
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