Officers responding to the call arrested a 14-year-old Te Awamutu boy who they found running down the road with a bag full of cigarettes and tobacco and a 16-year-old Hamilton boy who was found nearby, police said.
They did not find the third offender.
Mr Thornton said police were able were quickly able to locate two of the three offenders because the alarm had already been raised.
"His actions and those of the members of the public allowed us to respond in a timely manner and epitomise the saying; 'see something- do something'."
Police investigators would like to speak to the man who raised concerns about the boys acting suspiciously outside the station, Mr Thornton said.