A large area of sugarcane fields in Vietnam's central province of Phu Yen has been flooded and tons of harvested crop wiped away as three drunk men released water from a reservoir, local police said.

Police said they have identified the culprits in the sudden flood that flushed more than 2 million cubic meters of water through two communes in the province around midnight Wednesday.

The water loss is equivalent to the combined water volume of around 800 Olympic-sized pools.

The three young men had had too much to drink before they sneaked into a control station of the Suoi Vuc reservoir and pressed discharge buttons.

Nearly 20 hectares (49 acres) of sugarcane fields ready for harvest were submerged and 15,000 tons of harvested sugarcanes were gone in the rushing water.

Ten farmers who were packing sugarcanes in their field managed to jump to higher grounds, Dan Tri news website reported.

Local authorities have estimated the damage at VND300 million ($13,200), the report said.

Managers of the reservoir said there were four workers guarding the reservoir at the time but they failed to spot the intruders as they were at another station 800 meters away.

The three men are under investigation, police said.

The reservoir was built to hold around 10.5 million cubic meters. It went into operation in late 2015, providing water for local households and 790 hectares of rice and sugarcane fields.

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