They arrived at the Colombo international airport on a charter flight arranged by Australia.
On October 14, off Sri Lanka's southern coast, some five fishermen on a trawler were believed to have faced a pirate attack.
Later it was revealed that the hijacking of the trawler was a planned attack carried out by unscrupulous migration scam operators.
Three of the fishermen were found missing while two of them badly injured were rescued mid-sea by a merchant vessel.
The local police alerted the interpol after details emerged that the hijacking of the trawler was part of the immigration scam sending asylum seekers to Australia.
"We have been told that they were intercepted by Australian authorities on Thursday", a police spokesman said.
Police say they have arrested over 1,000 people since the beginning of the year for trying to leave Sri Lanka for Australia on board fishing trawlers.
