According to the regional Interior Ministry on Monday, the casualties were caused by the reckless handling of the grenade, which was brought to a computer class by a student, Xinhua news agency reported.
Ten of the injured have been hospitalized, with three of them in critical condition.
The student who took the grenade to the school has been detained and is being interrogated.
Dagestan is a hotbed of insurgency in the North Caucasus close to the conflict-ridden Middle East. Repeated violent attacks have plagued the region for years.
But it is still unclear whether Monday's blast was just an accident or linked to terrorism.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
Doraiah Chowdary Vundavally is a Software engineer at VTech . He is the news editor of SocialNews.XYZ and Freelance writer-contributes Telugu and English Columns on Films, Politics, and Gossips. He is the primary contributor for South Cinema Section of SocialNews.XYZ. His mission is to help to develop SocialNews.XYZ into a News website that has no bias or judgement towards any.
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