Tainted syrup medicine imported from India was the cause of an outbreak of kidney failure that killed more than 60 children in the West African nation of Gambia last year, according to a report by a team of international experts seen by Bloomberg.

The report, submitted to the Gambian health ministry earlier this year and not yet made public, is the most definitive statement yet on the cause of the episode. It contradicts the official position of Indian authorities, who insist that the country’s products weren’t to blame. A director for the Gambian ministry of health didn’t respond to calls and an emailed request for comment.

Although the committee was able to establish that a child drank the contaminated medicine from an Indian drugmaker, Maiden Pharmaceuticals, in only 22 deaths from so-called acute kidney injury, or AKI, it said that symptoms in 30 others were consistent with the poison’s effects and no other cause could be found.

It lacked enough information on 13 more cases.

“The outbreak of AKI in children in the Gambia is attributable to medicines contaminated with DEG/EG,” the committee concluded, referring to the two contaminants, diethylene glycol and ethylene glycol.

“We have made our stand clear that as per our testing, the product had no issue,” said Rajeev Raghuvanshi, the Indian drug controller general, in a text message to Bloomberg. He referred further questions to the health ministry, which didn’t respond to requests for comment. A representative of Maiden also didn’t respond to inquiries.

The Indian government this week imposed a new regulation requiring cough syrup to be tested by a government lab before it can be exported.Indian authorities have defended the drugs. In December, the Indian drug controller general at the time, VG Somani, told the WHO that his organization’s own tests of Maiden drugs found no contamination.