By Panu Wongcha-um, Patpicha Tanakasempipat and Aukkarapon Niyomyat
BANGKOK (Reuters) - An army general, two provincial politicians and police officers were among 62 people out of a total of 103 defendants found guilty on Wednesday by a judge in Thailand's biggest human trafficking trial.
The trial, which began in 2015, had been marred by allegations of intimidation of witnesses, interpreters and police investigators.
Some of those guilty of trafficking were also convicted of taking part in organized transnational crime, forcible detention leading to death, and rape.
A Bangkok court took more than 12 hours to deliver its ruling which rights groups said showed the government was serious about convicting perpetrators.
"The court has sentenced 62 defendants on 13 different charges," the criminal court said in a statement on Wednesday.
In the harshest sentence given by the court, Soe Naing, widely known as Anwar, a Rohingya man who police said was a key figure behind a brutal trafficking network that ran a jungle camp where dozens died, was sentenced to 94 years in prison.
The defendants, among them Myanmar nationals, were accused of smuggling and trafficking migrants on the Thai-Malaysia border.
Thailand has historically been a source, destination and transit country for men, women and children who are often smuggled and trafficked from poorer, neighboring countries, including Cambodia, Laos and Myanmar, to work in Thailand or further afield in Malaysia, often as laborers and sex workers.
Last month the U.S. State Department left Thailand on a Tier 2 Watchlist, just above the lowest ranking of Tier 3, in its annual Trafficking in Persons (TIP) Report, because the country did not do enough to tackle human smuggling and trafficking.
The convictions could help lift Thailand out of Tier 2 next year, said rights groups.
"This should potentially show that the Thai government will continue to pursue measures that will lift Thailand out of Tier 2 of the U.S. Trafficking in Persons (TIP) report," Amy Smith, an executive director of rights group Fortify Rights, told Reuters.
Prime Minister Prayuth Chan-ocha, head of the ruling junta, asked Thais not to blame the trafficking on military figures, a reference to the army general on trial, Manas Kongpan, the most senior of the officials arrested in 2015.
"There are many people in this human trafficking network," Prayuth told reporters. "Don't group all soldiers in the country as one."
Manas was sentenced to 27 years in prison.
The two convicted politicians, from provinces in the south, Patchuban Angchotipan – a former official in the Satun provincial government better known as "Big Brother Tong" - and Bannakong Pongphol - ex-mayor of Padang Besar in Songkhla - were sentenced to 75 years and 78 years in jail respectively.
The trial began in 2015 after a Thai crackdown on trafficking gangs following the gruesome discovery of dozens of shallow graves near the Thai-Malaysia border that authorities said was part of a jungle camp where traffickers held migrants as hostages until relatives were able to pay for their release.
Many never made it out. Some of the dead are thought to have been Rohingya – a persecuted Muslim minority from Myanmar's troubled Rakhine State – although Thailand has yet to release a full report on the graves and the results of post-mortem forensic testing.
Rights groups say trafficking networks were largely left intact by the 2015 crackdown and trial.
"We believe the crackdown is only a disruption of a trafficking network but that network is still very much well in place," said Smith.
Sunai Phasuk, senior Thai researcher for Human Rights Watch, said the death penalty could be the heaviest sentence for those convicted of trafficking.
"The fact that there are very senior officials charged with this crime will help deter criminals in trafficking networks in the future," Sunai, who observed the court proceedings, told Reuters.
Thailand denies that trafficking syndicates still flourish, saying it has largely stamped out human trafficking.
In its TIP report last month, the State Department said Thailand did not "convict officials complicit in trafficking crimes" and official complicity continued to impede anti-trafficking efforts.
(Additional reporting by Amy Sawitta Lefevre and Panarat Thepgumpanat; Writing by Amy Sawitta Lefevre; Editing by Michael Perry, Clarence Fernandez and Ken Ferris)