Four people died instantly after being struck by lightning in Papua New Guinea's Southern Highlands Province at the weekend.
Continuous rain, strong winds and lightning battered villages 18 kilometres outside of the provincial capital, Mendi.
The Southern Highlands Provincial Disaster and Emergency Coordinator, Martin Pat, says the event was unusual as the lightning struck horizontally and killed two women in their mid-20s, a middle-aged woman and a young boy on Saturday.
"Between three and 4pm the disaster struck a local market named Ekari. And it struck about 21 people who were there. At the market there was more than 400 plus people doing normal business, selling their produce and all these things. Out of the 21, four people were killed instantly."
Martin Pat says 17 people were treated in hospital and some required surgery.