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DARWIN - Two German tourists feared missing after visiting the Australian outback have been spotted on a boat tour in Western Australia.
The sighting has prompted police to urge travellers to stay in contact with friends and family and respect the vastness of the outback.
Holger Richter and Kathrin Kleinbauer, both 31, last spoke to friends on a mobile phone on June 19 while they were visiting Uluru in Australia's Red Centre.
The pair, who arrived in Australian in December last year on a 12-month working visa, told friends they planned to visit the Olgas before travelling to Darwin and then on to Perth.
They had been keeping in weekly contact with a Sydney friend, who reported them missing yesterday after they failed to arrive, as scheduled, at his niece's home.
Detective Senior Constable Kerry Harris today confirmed the couple were yesterday on a boat tour of Ningaloo reef, in Coral Bay, Western Australia.
"The operator reports that they were in good spirits and police from Exmouth will attempt to locate the couple," he said.
(But) we are still keen to speak to them directly."
Mr Harris also urged tourists to stay in contact with people when travelling across the vast stretches of outback Australia.
"It is imperative that people understand that given the vastness of Australia any person travelling in remote areas must have a fixed plan and regular contact points while travelling," he said.
"Changes of plans should be notified to avoid unnecessary concern for families and friends."
He also urged to travellers to ensure they were fully equipped to deal with any emergency situations."
This morning territory police said they would be contacting the couple's family because there had been no response from the public following the media coverage since early yesterday.
The last tourist to go missing in the Northern Territory outback was Queenslander Oswald Orman.
The 37-year-old was last seen trying to hitchhike along the Barkly Highway near the Barkly Homestead, 210km from Tennant Creek.
- AAP