BANGKOK — A Thai general is among more than 100 defendants facing a verdict on Wednesday in a sprawling 2015 human trafficking case which saw thousands of Rohingya and Bangladeshi migrants abandoned at sea and in jungle death camps.

Thailand’s administration launched a crackdown in May that year on a multi-million-dollar network running migrants through southern Thailand and onto Malaysia.

It unspooled a crisis across Southeast Asia as gangmasters abandoned their hungry and desperate human cargo in jungle camps and at sea in overcrowded boats which were then "ping ponged" between Thai, Malaysian and Indonesian waters.

Bangkok Criminal Court is due to begin reading verdicts for 103 defendants on Wednesday morning in what is expected to be a lengthy hearing.

They are accused of offences spanning human trafficking, ransom and murder - a charge that can carry the death penalty.

Army Lieutenant-General Manas Kongpan, a powerful figure in the security apparatus covering the south, is the highest-ranking official on trial.

He denies the charges.

The crisis emerged after Thai officials uncovered dozens of shallow graves in hidden camps dotting the steep hills along the Thai and Malaysian border area.

They revealed the horrors endured by migrants, who were starved and held in bamboo pens by traffickers who demanded ransom for their release.

The verdict is being closely-watched inside and outside Thailand. 

Amy Smith, from Fortify Rights, described the trial as "important and unprecedented".

The senior policeman who initially headed the probe, Major General Paween Pongsirin, fled Thailand under threats to his life.

Days before he left he said the case had been pulled before it could fan out further into the complicity of officials.

Stateless Rohingya Muslims have fled neighbouring Myanmar in their tens of thousands since sectarian violence flared in 2012.

They were joined by Bangladeshi economic migrants on a rickety boats southwards across the Andaman Sea, seeking work and sanctuary in Malaysia and Indonesia.

Thousands are believed to have died at sea, in a migrant flow that garnered few headlines until the trafficking crackdown in 2015.

The sea route south has been quiet since the crackdown. — AFP