The hatch door fell off, causing the contents of the planes hold to haemorrhage valuables.
A police spokesperson said that there were five crewmembers on board the plane and none of them were hurt in the incident.
Technical engineers at the airport who prepared it for take off have been detained although it's unclear if the incident was an accident or a deliberate attempt at a heist.
"At least 172 bars of gold weighing 3.4 tons have been recovered from the area", TASS cited an Interior Ministry source as saying. According to the Mash Telegram channel, the whole cargo is worth the hefty sum of 21.6 billion rubles (US$380 million). The investigative committee did not disclose the nature of the lost metal but Russia's eastern region is famous for its gold mines and diamond production.
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Most of the initial 88 aircraft are operational and have clocked more than 57,600 flight hours over 142 routes, the report added. Three other IndiGo A320Neo planes have been on the ground since February following similar engine failures.
Kupol mine where the cargo came from is operated by Canada-based mining company Kinross Gold.
The precious cargo started falling out of an An-12 plane shortly after it took off from the Yakutsk airport as its backdoor broke off.
Local witnesses reported that the photos were gold, platinum, and gems.
Local residents were hit with "gold fever" after receiving news of the blunder, according to local media reports.