A Canadian and an Indonesian have been ordered back to jail for committing sex abuse at a Jakarta international school after their acquittals were overturned, prompting fury on Thursday from Canada at the "unjust" decision. The Supreme Court in Jakarta said it had on Wednesday thrown out the acquittals handed down by the high court in the case of administrator Neil Bantleman, who also holds British nationality, and teaching assistant Ferdinand Tjiong. The staff from the Jakarta Intercultural School (JIS) were jailed in April last year for 10 years each after a legal process criticised as fraught with irregularities, but were freed several months later when their convictions were overturned on appeal. But prosecutors appealed, and the Supreme Court reinstated the convictions for abusing young children and increased their sentences to 11 years, said court spokesman Suhadi, who like many Indonesians goes by one name. "We believe Jakarta high court made a mistake in applying the law," he told AFP, adding the judges decided the evidence in the original case had been "sufficient and convincing". Tjiong was returned to jail early Thursday but authorities are still looking for Bantleman, said the South Jakarta district attorney's office. Both men have maintained their innocence, and received backing from Jakarta's expatriate community, foreign governments and the school, which has been a favourite with foreigners and wealthy Indonesians for decades. Supporters accuse police of a botched investigation, allege the original trial was unfair, and say much of the evidence was suspect. After news emerged of the Supreme Court ruling, Canadian Foreign Affairs Minister Stephane Dion said his government was "deeply dismayed and shocked". “This decision is unjust, given the many grave irregularities throughout the various proceedings in this case and the fact that all evidence presented by the defence has systematically been rejected," he said in a statement. "Mr. Bantleman and Mr. Tjiong were not provided the opportunity to demonstrate their innocence. Despite Canada’s repeated calls for due process, this case was not handled in a fair and transparent manner." - Questions over rule of law - The United States has also been outspoken in its criticism of the case, and the American ambassador in Jakarta, Robert Blake, warned the latest court ruling could affect Indonesia's reputation overseas. "The international community continues to closely follow this case. The outcome of the legal process will impact international views about the rule of law in Indonesia," he said in a statement on the US embassy website. Chandra Saptaji, spokesman for South Jakarta district attorney's office, confirmed Tjiong had been returned to jail but added authorities were still looking for Bantleman. When prosecutors appealed the acquittals, authorities ordered Bantleman to remain in Indonesia. Rully Iskandar, a spokesman for JIS, said Bantleman's travel ban was supposed to remain in place until the end of February, pending the Supreme Court decision, but gave no indication where he was currently. "We have been communicating with Neil's and Ferdi's family and of course they were shocked, this is unexpected," said Iskandar. Five Indonesian cleaners were also jailed last year for committing sexual abuse at JIS. Their lawyers claim they are innocent. The scandal began in 2013 when accusations were directed at the cleaners at the school before allegations were levelled at Bantleman and Tjiong. The expatriate community in Jakarta was initially shocked at the claims of abuse, but horror quickly transformed into concern at what supporters say was an unfair attempt to target Bantleman and Tjiong by Indonesia's notoriously corrupt police and judicial system.