An unknown number of people were believed to be on the run in a crocodile-infested region of north-eastern Australia after a fishing boat ran aground on Sunday, authorities and reports said.
An illegal fishing vessel was located in the vicinity of Daintree River, a mangrove estuary in Far North Queensland state, the home affairs department said.
"We can confirm that 11 people have been located. The first priority is to confirm the safety and welfare of the people on the fishing vessel," the department added in a statement.
The department did not respond to questions of whether the vessel was carrying asylum-seekers, illegal migrants or fishermen.
Brisbane's Courier Mail and commercial television broadcaster Channel Seven said those on board were either asylum-seekers or illegal immigrants.
Channel Seven said those found were Indonesian, while The Australian newspaper said they were believed to be Vietnamese, adding that up to 40 people were believed to have been onboard the vessel.
A local tourism operator said he had seen an empty boat that "looked like Chinese junk".
"Apparently, other boaties were saying over the radio, it was adrift and before that people were seen leaving it and running off into the bush," David Patterson told national broadcaster ABC.
"We saw this boat and didn't think a lot of it really, then after the radio chatter (we heard) it was deserted and people were seen leaving it."
If the boat was carrying asylum-seekers, it would be the first time in four years that such a vessel has reached Australian shores.
Asylum-seekers who try to reach Australia by boat are either turned back or sent to remote Pacific camps where conditions have been widely criticised.
They are blocked from resettling in Australia.