GENEVA (AP) — FIFA is investigating Zambian officials over allegations they allowed eight players banned for match-fixing in a notorious case in Finland to return to football without permission.

FIFA said Friday it opened a disciplinary case and invited the Football Association of Zambia to provide an explanation "together with any documentary evidence it might deem appropriate."

"The players were all suspended by the Finland Football Association for match-fixing offenses and these sanctions were extended as to have worldwide effect by the chairman of the FIFA Disciplinary Committee," football's world governing body said in a statement.

FIFA said it believes at least four of the players — who were not identified — appeared in official matches in Zambia.

In 2011, nine Zambian players received suspended sentences of at least six months from courts in Finland.

Seven players from RoPS team in Rovaniemi and two from AC Oulu were linked to taking bribes from Singaporean fixer Wilson Raj Perumal to help Asian organized criminals arrange betting coups.

Perumal was arrested in Finland in February 2011 and later jailed after a criminal trial.

Now co-operating with authorities in Hungary, Perumal has given evidence which is key to FIFA and law enforcement agencies piecing together the scope of match-fixing plots worldwide carried out by crime syndicates with Singapore connections.

FIFA and Interpol have urged governments worldwide to help fight match-fixing, as football authorities have limited investigative powers and jurisdiction only over people within the sport.

The Finland FA banned the Zambian players through April 5, 2013, and FIFA extended those sanctions globally.

FIFA said Friday that the FAZ took over eight players' registration from Finland without proper documents and while they were suspended.

The case is embarrassing for Zambia which raised its profile by winning the 2012 African Cup of Nations, and placing its most senior official in high-ranking FIFA positions.

FAZ President Kalusha Bwalya, a former playing great, is a member of the FIFA Football Committee and served in 2011-12 as deputy chairman to Franz Beckenbauer on FIFA's Task Force Football 2014.