North Yorkshire Police were alerted to reports of two men behaving suspiciously last night.
Members of the public altered police to the men around Snainton and Ebberston, on the A170 west of Scarborough, at about 5.30pm on Monday April 29.
Officers began an immediate search of the area, including with a police drone, and spoke to a number of people, but no suspects were located.
Separately, officers conducting the search found a discarded kitchen knife and sunglasses, which were seized and will be disposed of appropriately.
A spokesperson said: "We're very grateful for the calls from the members of the public, who did exactly the right thing by contacting us to report suspicious activity in their community - and we would urge everyone to follow their example.
"Particularly in rural areas, using the 101 non-emergency number to contact North Yorkshire Police will help us prevent crime and piece together enough information to bring offenders to justice. "