HANOI - As many as 29 among 30 death sentences were upheld for appellants involved in Vietnam's biggest drug case ever.

Vietnam's Supreme People's Court during an appeal trial held in Vietnam's northeastern Quang Ninh province earlier on Thursday commuted one death sentence to life imprisonment, reported Vietnam 's state-run news agency on Friday.

The appeal court was held for the case of illegally trafficking and trading of over 5,000 heroin cakes involving 89 defendants.

Altogether 30 death sentences, 13 life imprisonments and punishment from warning to 20 years imprisonment were announced by Quang Ninh Provincial People's Court at the first instance trial held in January.

The defendants were charged with illegally buying and selling drug, illegal business, falsifying documentation of agencies and organizations, forging in the work, giving bribes and being brokers for bribery, reported VNA.

Of the 89 defendants, a total of 40 appealed for reduction of punishment.

The case was discovered in late 2013, involving a trafficking ring set up in Vietnam, Laos and China, VNA quoted police as saying.