Fiji police say those living in flood-prone areas in the Western Division should move to higher ground due to flooding.
The police put the statement on social media just after 4pm, local time.
Assistant Commissioner of Police Operations Livai Driu said continuous rain from morning has seen flooding in some areas.
"For precautionary measures, we are urging people to move to higher ground now or to an evacuation centre," he said.
"People need to move now before it gets dark. Moving at night will be a big risk for them and for our officers on the ground."
He said teams are on standby at police stations and they will assist in moving people to higher ground.
The Western Division Command and Coordination Center can be contacted on 9905457 should anyone need assistance in moving to higher ground.
Meanwhile, the Fiji Roads Authority said about the same time that Nadi Town was flooded and impassable to all traffic.
Multiple other roads in the Western Division were closed, or partially closed - meaning only accessible with a four-wheel drive.
The country's National Disaster Risk Management Office advised communities to continue taking necessary precautions to ensure safety, as another active trough of low pressure was expected to approach Fiji from the west on Boxing Day.
It said it had received reports of flash flooding and landslips.
A heavy rain warning was in force for the whole Fiji group from the Metservice. The alert was due to be updated late in the evening of Christmas Day.
The Metservice said 130mm of rain fell in the 24 hours from 3pm Christmas Eve to 3pm Christmas Day at Nadarivatu.

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