The fighting broke out on Monday after police blocked some 500 jade scavengers from accessing an industrial mining plot in northern Kachin state -- the heart of Myanmar's shadowy multi-billion dollar gem trade.
The group attacked officers with hammers and stones, leading police to fire "warning shots", the report said.
The fighting outside the town of Hpakant left two migrant workers from western Rakhine state and one officer dead, with nine workers later arrested for their alleged involvement in the unrest.
In recent years impoverished workers from across Myanmar have poured into the area to scour the rubble for any hunks of precious stone passed over by the mining giants.
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Clashes are common, with security forces trying to keep itinerant workers off company land.
Last month five people were killed after police opened fire on a group of prospectors trying to enter a different mine in Hpakant.
Deadly landslides also pose a danger during the monsoon season, with one of the worst incidents in 2015 leaving more than 100 dead.
The vast majority of the stone is shipped to neighbouring China where there is voracious demand for jade, which is considered lucky.
The jade industry -- which was sanctioned by the US until last October -- has also fuelled unrest between Myanmar's powerful military and ethnic rebels in insurgency-torn Kachin, both of whom are believed to profit from the trade.