LG’s "G in the Cloud" promotional event in Seoul on Friday resulted did not get LG the press coverage it wanted as the event ended in 20 being injured.

Twenty people were injured when a promotional stunt in Seoul for LG’s new G2 smartphone went wrong, according to the Korea Times newspaper.

Hundreds of helium balloons were launched at the event, with 100 of them containing vouchers for a free G2 handset.

But in a clamor to get their hands on the free phone vouchers, people tried to grab the balloons by bursting them with BB guns and spears.

Reportedly, 20 people were injured in the incident, some as a result of being shot with BB guns.

Some of those hurt in Seoul on Friday were hospitalised, and LG has said it will cover related medical costs.

In a statement, the company said that other planned events had been called off because of safety concerns.

One regional TV channel has dubbed the scrum "World War G" in comparison to the film World War Z.

In South Korea the new G2 phone, which was unveiled last week, retails at $850.