16 people were killed at the First Pangyo Techno Valley Festival, an open-air pop music concert in South Korea, when the cover of a ventilation shaft they were standing on gave way.
The spectators fell 20 metres into an underground parking area. They had been standing on the grate to try to get a better view of 4Minute, a popular K-pop girl band, who were on stage performing at the time.
Police officials examine the cover of a ventilation shaft that gave way during the music festival, killing 16(Reuters)
Policemen stand guard near a broken ventilation grate after concert goers fell through it into an underground parking area in Seongnam City(AFP)
An image posted on Twitter shows concert-goers standing on the grate.
About 700 people were at the outdoor concert near a shopping mall in Seongnam, just south of Seoul, where the group 4Minute were among the acts performing.
The group features the singer and dancer Hyuna, who shot to fame after performing in the "Gangnam Style" music video by the South Korean rapper Psy.
The YTN television network, citing unidentified witnesses, said many of the spectators were female students. The victims weren't immediately identified.
The cause of the accident wasn't immediately known. "The injured are in serious condition so the number of deaths could rise," said an emergency services official.

People who went to the concert was amusing themselves but all in a sudden people on the ventilation fall beyond 20meters underground. 
We all agree that there is no doubt that this is a terrible accident and we should care for families who lost their beloved. However, we can question that why did so many people had to stand on that unsustainable ventilation. People all know that it is not safe to stand on it, however many people insensitively stood on and the disaster happened. 
The trend of public opinion on online says that this accident should be blamed to the people who stood on that ventilation. They all agree that it is a sad accident but, the concert managers should not be punished nor blamed for it. 
I also think the same, the victims of the accident should not have gone up to the ventilation in the first place we all know that it is not safe to stand up there. I would say that it was the insensitivity of people which caused the accident to happen.
I would like to ask few questions to the people whoever reads this post. 
Should the manager and directors of the concert  should be blamed?
How can we make people be more careful about this kind of accidents?
Do you agree with the public opinion?