Leaders of the search for US adventurer Steve Fossett further scaled back the aerial operation yesterday but insisted they were not giving up.

As the search for missing aviator Steve Fossett enters its sixth full day concern is growing as the unprecedented effort drags on with no clue about his possible location.

US National Guard C-130s and helicopters with infrared and thermal imaging equipment scoured the soaring peaks and sagebrush desert of north-west Nevada early today for any sign of missing adventurist Steve Fossett.