The balloons explosion incident in Dataran Putrajaya last Saturday was caused by the use of hydrogen gas in the balloons, said Putrajaya district police chief ACP Rosly Hasan.

The explosion of balloons had resulted in 16 people suffering minor injuries including nine children.

He said police had opened an inquiry paper to find the root cause of the incident that occurred at the end of the Education Ministry's 2019 national sports month event last Saturday.

Earlier reports suggested that the balloons were filled with helium gas. 

The incident was believed to have occurred when someone tried to cut the string tied to a bunch of balloons with a cigarette lighter, and the flame is believed to have struck one of the balloons before the whole bunch exploded.

“It was filled with hydrogen, not helium. Hydrogen is highly sensitive and extremely flammable,” Rosly said adding that police had also found a cigarette lighter at the scene.

On the latest update on the victims, he said as of 10 am today, two men and two women were still receiving treatment for second-degree burns at the Putrajaya Hospital. 

They were among the six victims, including an eight-year-old girl admitted to the hospital after the incident.

Ten others received outpatient treatment.

- Bernama