"Most of the people were brought unconscious with symptoms of drug overdose to the hospital where many of them died. Thirteen people have died in the civil hospital since Dec 20, 2012," Aizawl Civil Hospital's Emergency department medical officer Jeremy Pachuau told reporters.
"Some of the people were cured by administering antidotes while some died as their treatment started too late," the official added.
Pachuau said that in the preliminary study seemed most of the cases were due to consumption of cough syrup spiked with grape wine which could produce dangerous chemical reactions.
Cough syrup, which contained high dose of codeine and other drugs, is frequently used as an intoxicant among young people in the northeast.