Transcript for Lightning Danger: Run for Cover
well, last night here, we learned of just the latest kate of children being hit by lightning. This time near indianapolis. Tonight, one of them is still in critical condition. It turns out there was no warning, because that storm was several miles away. So tonight here, abc's neal karlinsky with important lessons about lightning for you and your family. Reporter: For the second time in just a week, normal summer active pitches have put children in the crosshairs of a lightning storm. This time, at a summer camp in indianapolis, where witnesses say there wasn't even a storm in the area. I feel so sorry. There's nothing you could prepare, because the sky didn't even get dark. Reporter: Three children were hurt and sent to the hospital, where one remains critical tonight. But with no storm to warn them, what happened? The sky was blue, but then we had the thunderstorm that the lightning came from, probably about three to five miles away from that storm and that's not entirely unusual. Reporter: It comes less than a week after nearly two dozen boy scouts were injured by a lightning strike in new hampshire. I blacked out for maybe five seconds and when I come to, I'm just, like, shuddering, I'm numb and I can't feel much. Reporter: Thunderstorms can generate lightning that can hit up to 25 miles away. Feeling safe just because it's not raining out is a myth. And while the vast majority of strikes happen in open fields like this week's accident, staying low to the ground to stay safe is also a myth. Certainly, don't want to be outside. Don't want to lay flat. That's actually not the greatest option. Reporter: Bottom line, there's only one truly safe place to be in the event of lightning. Indoors. Neal karlinsky, abc news, seattle.
This transcript has been automatically generated and may not be 100% accurate.