A third crocodile has been caught as police continue to investigate a suspected fatal attack on a man in far north Queensland.

Arthur Booker, 62, went missing last Tuesday after he went to check crab pots in the Endeavour River near Cooktown.

The Environmental Protection Agency (EPA) advised police on Monday that a third crocodile had been captured in a trap in the river.

EPA officers examined a crocodile in Cairns on Sunday, but failed to find any evidence that the animal had killed Booker, a Vietnam veteran from Logan south of Brisbane.

The other two captured crocodiles are also to be x-rayed.

Police said there had been no other developments in the investigation on Monday.