Newly released court documents say a Canadian teen who pleaded guilty in a terror plot to attack New York City landmarks has suffered from drug addiction and mental health issues.

Letters from a New York prosecutor filed with an American court show Abdulrahman El Bahnasawy tested positive in prison for a prescription drug used in opioid-addiction treatments, a finding that led to the loss of family visitations for a period of seven months.

The letters also say a psychiatrist visited El Bahnasawy in prison, but materials related to both his drug addiction and his mental health issues are redacted.

On Friday, officials in the U.S. released details of El Bahnasawy’s guilty plea, which was heard by a New York court last October.

The 19-year-old from Mississauga, Ont., pleaded guilty to multiple terrorism-related charges, but the records were sealed as federal agents worried about tipping their hand to two other suspects who were outside the country.

U.S. authorities allege the three men communicated through Internet messaging applications, allegedly plotting to carry out bombing and shootings in heavily populated areas of New York City during the Islamic holy month of Ramadan in 2016.

El Bahnasawy is scheduled to be sentenced in December.

The Canadian Press