Hughie Morton, 21, and Troy Mathieson, 23, were last seen on Ross River Road near floodwaters on Monday morning.
Yahoo7 News understands the pair were attempting to evade police after they allegedly tried to loot a Dan Murphy’s liquor store.
The pair had not been located by Monday night despite extensive inquiries with family and friends, and a search of floodwaters and the area has begun as a precaution, police say.
Meanwhile, thousands of other people have been evacuated and hundreds of homes inundated by water.
An emergency alert was issued for Bluewater, Bluewater Park, Toolakea and Saunders Beach, northeast of Townsville, early on Tuesday morning.
Residents were advised to move to higher ground.
Townsville remains the hardest-hit area although floodwaters are affecting communities as far west as Mt Isa, in the state’s interior.
The one-in-100-year deluge has caused catastrophic flooding as rivers and creeks burst their banks, spilling water through streets and consuming entire suburbs.
A large number of #warnings are currently in place across #Queensland and many of them relate to #flood. This map gives some sense of the scale of what's happening and where. You can keep up to date on all the current warnings https://t.co/Ag6ekuAjQd pic.twitter.com/o7fRMl9d6Q
— Bureau of Meteorology, Queensland (@BOM_Qld) February 4, 2019
The vigorous monsoon trough dumping the rain has begun moving south but it is unpredictable, and dangerous conditions are expected to continue for at least the next 24 hours.
Late on Monday, a severe weather warning remained in place from Ingham to Mackay and west to Cloncurry, although lower than expected rainfall throughout Monday has eased conditions in Townsville.
Water levels in the Ross River Dam dropped to 211 per cent of capacity, down from 250 per cent earlier in the day.
Further heavy rainfall is likely to develop in the severe warning area on Tuesday, with six-hourly rainfall totals of between 150mm and 200mm possible, the Bureau of Meteorology said.
“Mackay could get some heavy falls over the next few days with some possibility of flooding,” meteorologist Jess Gardner told AAP.
Inland, the rains have brought “tears of happiness” to the parched outback, where drought conditions had brought many graziers to their knees.
Dry rivers are again flowing where a week ago, it was just dust, Cloncurry Mayor Greg Campbell said.
“It is a great relief to the community. The old timers always say the only way to break a drought is with a flood,” he said.
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