Initial investigation showed that a heater in the opium rehab camp in Langarud in the Caspian Sea province of Gilan was the cause of the fire that spread to the rest of the centre, the province's deputy governor was quoted as saying by the semi-official Fars news agency.
"The manager and other possible culprits have been arrested so that the cause of the incident is more accurately determined," the Tasnim news site said.
According to the United Nations Office of Drugs and Crime, Iran has one of the severest addiction problems in the world.
The blaze started shortly before 6 a.m. local time in the coastal city of Langaroud, according to IRNA, an Iranian state-owned news agency. It said that four of the injured were in serious condition.
Unverified video posted by ISNA, the Iranian student news agency, showed a large ball of flames and smoke rising in the sky along an urban road.
An initial investigation determined that a heater had sparked the blaze, setting a curtain on fire that spread to the rest of the building, according to the Fars News Agency, which is affiliated with the Islamic Revolutionary Guards Corps.
Mohammad Jalai, the deputy governor of the province where the blaze occurred, told Fars that the manager of the rehab center and other “related officials” had been arrested in connection with the fire. He blamed overcrowding at the facility for the high toll, Fars reported.
Iran has long grappled with severe rates of addiction, which the United Nations has estimated are among the highest in the world. The country sits on a main smuggling route for heroin and opium, primarily coming from Afghanistan to Western Europe.
Some drug offenses are punishable by death in Iran. At one point, possession of as little as 30 grams of heroin was enough under Iranian law to face execution by hanging, though in 2017, the country significantly raised the bar for the mandatory imposition of the death penalty, according to Human Rights Watch.
However, a June report from Amnesty International said that the Iranian authorities had executed at least 173 people convicted of drug-related offenses this year, calling it a significant increase from 2022. Executions for drug-related offenses made up two-thirds of all the executions carried out in Iran in the first five months of 2023, according to Amnesty.
