He is the man in charge of the search for Ben Needham, the British toddler who disappeared on the island of Kos in 1991 and who is rumoured to have been taken to Katerini.
Chief Kiriakakis is no longer hopeful of finding Ben, who would now be four years old. After an anonymous tip-off to a hotline telephone number and a subsequent reported sighting of the boy in a gypsy encampment had given fresh impetus to the hunt, the police say they now have no solid leads.
They have given themselves another week before abandoning the search altogether. Mr Kiriakakis has 25 officers from a total police force of 250 looking for Ben, despite having serious reservations about the quality of the information that prompted the search.
The idea that a blond northern European boy is being raised by a Greek family here seems scarcely credible to many townspeople.
Like the Italians, the Greeks adore children, and the publicity surrounding Ben's case has hit a raw nerve in this town as in the rest of the country. Many people accused the British of racism and there are fears that publicity about a missing child could hurt the lucrative tourist trade.
Ben Needham vanished on the island of Kos in 1991 while his parents were holidaying. He was 21 months old. The parents, Kerry Needham, 23, and his father, Simon Ward, have been back to Greece on several occasions to search for the boy.
A pounds 20,000 reward has been offered for information leading to his return. When a hotline sponsored by Britain's National Missing Persons Helpline was opened in Greece over a month ago, one particularly insistent caller claimed to have information and wanted to know how he could get the reward money without anyone knowing his true identity.
Calling himself 'Andoni', he claimed that Ben had been renamed Andreas and was living with a man named Nikos, aged between 45 and 50. The informant said that Ben and Nikos were in south-east Katerini in a house with a front garden with two large trees.
But the trail appears to have gone cold despite intensive efforts by the Katerini police and the separate attempts of a British television producer and trustee of the Missing Persons Helpline, Caroline Mylon, to find Ben.
A spokesperson for the Missing Persons Helpline in Britain said that the police were in constant contact with Andoni, the anonymous informant, but were reluctant to go public with this information.
In Alexander the Great street, the main pedestrianised shopping district of Katerini, with its Body Shop and Benetton and toy stores, many of the evening strollers last week had heard from television reports that there was an effort under way to trace Ben, but they did not know that their own town was now the focus of the investigation.
Katerini, in the shadow of Mount Olympus, has a population of close to 70,000 and is relatively prosperous, thanks to the export trade in kiwi fruit and almonds from the surrounding countryside. It is also a low-cost tourist destination for East Europeans.
Xanthi Mavroedis, a travel agent, said: 'I feel terrible for the child's parents, but it seems unbelievable that the child could now be here three years later without anyone noticing.'
Willy Mirliavntas, an economist and consultant, said there was hardly any crime in Katerini. There had been only two murders the previous year, both crimes of passion.
'Perhaps the person who said Ben is here is just trying to get their hands on the reward,' he said. His reaction, like that of many, was a mixture of sympathy for the family and annoyance that Greece was once again the focus of unhelpful media attention in Britain.
In the background is a fear that Greece will eventually be portrayed as an unsafe place to bring children on holidays.
Greeks are already sore with the British media because of a long run of negative articles about Greece, focused mainly on the country's politics and its attitude to its northern neighbours, Albania and Macedonia.
Some now see a danger that Ben's case will add unfairly to the negative image. 'The attitude of many British papers towards Greece is unfair and at times racist,' said Mr Mirliavntas. 'Greeks are starting to feel under attack.'
Meanwhile, Chief Kiriakakis has his officers discreetly combing city neighbourhoods and outlying villages. Hundreds of posters showing what Ben may look like today have been distributed.
On Friday afternoon, on the edge of town, two policemen pulled over a man driving a motor scooter. He was not wearing a helmet and had a small boy of about four sitting between his legs. After checking the boy, then warning the father about the dangers of what he was doing, they let them go.
Other officers are checking village and town hall registers looking for an entry of a child named 'Andreas', the name Ben was said to be going under.
'We're going to all this trouble for the sake of the parents, because we feel sorry for them,' Chief Kiriakakis said, 'but you have to realise it's been three years since the boy went missing.'