The pandemic has driven an unprecedented boom in online business in South Korea, but that has come at a sobering cost.

15 delivery workers have died so far this year.

Their families blame health failure caused by extreme overwork.

Johnson Rock works 14 hours a day without a lunch break to deliver hundreds of boxes.

Today, I'll additional 15 people already dead, which is very ironic because we're not working to die but to live.

How do you lead on the move?

Many delivery workers are denied safeguards and basic benefits such as minimum wage, overtime or insurance.

Most are classified as self employed, hired under what some refer to as Gap Jill contracts.

It's a legal blind spot that effects around 8% of South Korea's workforce, says Kim Tae wan, the leader of a union of 5000 careers.

There are many gap You'll contracts while general workers are guaranteed by employment.

Contract delivery workers cannot be protected because we are treated a self employed that leaves us exposed to abuse of power.

Labor officials say Cut throat competition adds pressure to cut delivery fees, which average is 72 cents per package.

Activists compiled accounts of those whose deaths have been attributed to the system.

Some developed breathing problems and chest pains leading to heart failure or, in at least one case, suicide.

Public outcry prompted apologies from big firms and acknowledgement from South Korea's labor minister, but many hold out little hope of change at a time of record unemployment.

Meanwhile, logistics firms are cashing in.

Hanjin Transportacion Sang Rocks Company posted a 35% increase in first half year operating profit.