Why smokers suffered seizures after puffing on 'tuklaw' or black cigarette

Some smokers went into seizures and shook violently after smoking black cigarettes, known locally as tuklaw. In a viral video, another smoker stiffened and cried after puffing tuklaw. Why?

Why smokers suffered seizures after puffing on 'tuklaw' or black cigarette

Some smokers went into seizures and shook violently after smoking black cigarettes, known locally as tuklaw. In a viral video, another smoker stiffened and cried after puffing tuklaw. Why?