By Geraldine Coughlan BBC correspondent in The Hague

A Dutch appeal court has increased the sentences of seven men convicted of belonging to a people-smuggling network responsible for the deaths of 58 Chinese immigrants two years ago.

Perry Wacker: Sentenced to 14 years in the UK

The victims suffocated in the back of a lorry as they were being smuggled into the UK through the port of Dover.

The so-called "brains" behind the operation, Grussel Oezcan, received the longest sentence - a ten-and-a-half year jail term.

But his right-hand man, Haci Demir, had his sentence reduced from nine to five years, because the judges said he showed remorse.

The lorry driver, Perry Wacker, was sentenced separately to 14 years in jail by a court in England last year.

'Snake heads'

Prosecutors in the Netherlands had demanded sentences of between seven and 20 years for manslaughter.

But the court ruled there were no grounds for this charge, which the men - all Dutch nationals, including two of Turkish origin - escaped at their initial trial.

In Rotterdam last year, the men were given prison terms ranging from six months to nine years, on charges of being accessories to manslaughter, human smuggling and belonging to a criminal organisation.

They were found guilty of arranging the illegal transport of the 58 Chinese immigrants and of failing to ensure there was adequate ventilation inside the lorry.

The public prosecutor described these men as "sub-contractors" in the human trafficking ring.

Earlier this month, police in Rotterdam arrested nine Chinese nationals whom they believe were the "snake heads" or ringleaders of the gang, which smuggled refugees from China, via Eastern Europe, for a fee of $30,000 each.

The police say there is no evidence to link these latest arrests with the Dover tragedy, but they believe they have now dismantled the network responsible for it.