Police are asking grey nomads across Queensland's far north to keep an eye out for two people missing for almost four days.
Vanessa Jane Cross, 40, and Wayne Henry Hutchinson, 45, were last seen by neighbours in the Cairns suburb of Mount Sheridan on Monday night.
Police say they're likely travelling in Mr Hutchinson's white Toyota Landcruiser but no one has any idea where the pair might be.
"After three days they could be a very long, long way away," Detective Acting Inspector Jason Smith told reporters in Cairns on Thursday.
"We're engaging police and the community from the tip of Queensland, out west and down south."
Neither has made contact with family and friends.
This is particularly out of character for Ms Cross who has two children under 16, and who has been described as a good mother.
The pair used to be in a relationship but are now friends.
Police believe they may have gone camping, although they can't verify if camping gear has been taken from Mr Hutchinson's home.
Other personal items are missing.
Police across the state's far north have been alerted and officers are checking camp sites throughout the region.
Officers are also asking grey nomads and other travellers to keep an eye out for a 2003 Toyota Landcruiser Prado with licence plate 055SVQ.
Both Mr Hutchinson and Ms Cross had recently requested to take leave from work.
Insp Smith says there's no evidence of foul play but investigations are continuing.