Ex-warlord Jean-Pierre Bemba's political party on Saturday announced it would appeal a decision to reject his candidacy in Democratic Republic of Congo's upcoming presidential elections.Late on Friday, the election commission had ruled out Bemba running on the basis that he had been "convicted by the International Criminal Court" in March 2018 for bribing witnesses. He was handed a year-long prison term and a 300 000 euro fine.But the court, which is based in The Hague, had overturned Bemba's conviction for war crimes and he returned to the capital Kinshasa in August after being acquitted.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and FacebookFollowing the late-night decision, Bemba's supporters vowed to mobilise with the head of his Movement for the Liberation of the Congo (MLC) telling AFP the party would lodge an appeal at Constitutional Court by Tuesday morning."We will use all the legal means at our disposal to defend Jean-Pierre Bemba's candidacy for the presidency," MLC secretary general Eve Bazaiba said.By Saturday morning, Congolese riot police, who are rarely seen on the streets, had deployed near the headquarters of the RTNC national radio and television in Kinshasa, where Bemba remains very popular."It's an operation aimed at discouraging (violence), it's an anticipatory move," police spokesman Colonel Pierrot-Rombaut Mwanamputu told AFP.Six candidates barred Ahead of the electoral commission's announcement, DRC opposition groups had accused the government of President Joseph Kabila of seeking to "exclude" multiple opposition candidates.In a statement signed by Bemba and exiled opposition politicians Moise Katumbi and Felix Tshisekedi, they urged Kabila to free up the electoral process and "stop giving injunctions to the election commission."Alongside Bemba, another five candidates were also rejected out of a total of 25 who had registered to run in the presidential elections, set for December 23.Among them were three of Kabila's former prime ministers - Samy Badibanga, Adolphe Muzito, and Antoine Gizenga."These exclusions are unacceptable and show once again that the electoral commission is totally dominated by Kabila," Katumbi wrote on Twitter.A former governor of Katanga who joined the opposition in 2015, Katumbi - who has been living in Belgium since 2016 - said he had been blocked from returning to register his candidacy. Considered a fugitive by the Ministry of Justice, Katumbi has been sentenced absentia to three years in prison with an international warrant out for his arrest. The six candidates have 48 hours to appeal to the Constitutional Court. The election commission must publish a final list of candidates by September 19.Suspicion On August 8, Kabila - who had held office since 2001 - signalled he would not run again, easing months of tension over his ongoing tenure.He has thrown his support close ally Emmanuel Ramazani Shadary, a former interior minister who is permanent secretary of Kabila's People's Party for Reconstruction and Democracy (PPRD).But DRC's opposition, which has shed blood in protests against Kabila's grip on power after his mandate formally ended in 2016, remains deeply suspicious.It has raised concerns about nuts-and-bolts issues such as the electoral roll and voting methods, and fears Kabila is simply plotting to remain the power behind the throne.A country of some 80 million people, DRC has never known a peaceful transition of power since gaining independence in 1960.Kabila took over from his father, Laurent-Desire Kabila, after he was assassinated by a bodyguard.Failed bid in 2006 His tenure over the vast mineral-rich country has been marked by corruption, inequality and unrest. The watchdog Transparency International ranked it 156 out of 176 countries in its 2016 corruption index.Bemba lost presidential elections to Kabila in 2006 and was later accused of treason when his bodyguards clashed with the army in Kinshasa.In 2007, he fled to Belgium, where he had spent part of his youth.He was then arrested in Europe on a warrant by the ICC for war crimes committed by his private army in neighbouring Central African Republic from 2002-3, when its then-president Ange-Felix Patasse sought help to repel an attempted coup.He was sentenced in 2016 to 18 years behind bars before his conviction was overturned on appeal in June.The ICC said Bemba could not be held responsible for crimes committed by his troops.