The arraignment of the suspects looks set to take place this week.
Suspects Zaw Lin and Win Zaw Htun, however, insist they were forced to confess to crimes they did not commit.
The two Britons were brutally killed on Koh Tao, a usually idyllic island in Surat Thani province, on September 15.
The suspects were illegal migrant workers on the island at the time the shocking crimes took place.
The source yesterday said a public prosecutor working on the case insisted there was incriminating evidence against the two Myanmar suspects.
“Procedures followed by investigators are also in line with laws. At first, they just charged the two Myanmar suspects with illegally entering Thailand. Murder charges have been pressed only after solid evidence emerged against them,” the prosecutor was quoted as saying.
The source did not identify the public prosecutor by name. Both local and foreign institutes have conducted DNA tests on the investigation into the Koh Tao crime and their results point fingers at the accused, the source alleged.
While Thai police insist they solved the case with legitimate evidence, speculation has been rife on social media that the two Myanmar men are just scapegoats.
Tawatchai Seangchaew, who heads the Office of State Attorney Region 8, said yesterday that lingering doubt among social-media users may stem from the fact they have not seen all the evidence.
“When the case reaches the court, the two suspects will be brought to the courtroom. There, they can plead innocent or guilty. And the court will handle the rest,” he said.
Tawatchai said parents of the victims would be notified about the progress in the case before the hearings start.