Three people have been killed by an explosion near a shopping center in the Russian city of Makhachkala, Dagestan. Two of them were killed instantly, one other died in hospital.

Police say the bomb was packed into a box or a bag and two teenagers were killed as they tried to uncover the dangerous object.

The two injured were their friends, also teenagers. One of them died in hospital a few hours later.

The blast took place shortly after midday local time near a local market and a shopping center.

"Preliminarily, we believe it was a piece of metal pipe with explosives inside equal to approximately 2kg of TNT," RIA-Novosti quotes a police source as saying.

Police are investigating information that the object that later exploded had been thrown at the entrance of the shopping center from a passing car. 

Photo from twitter.com user @Nur_Mag

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