The third round of the PGA Tour Championship was underway at the East Lake Golf Club on Saturday when organizers suspended play due to inclement weather, the PGA said.

"The safety of our fans, players and partners is of the utmost importance," the statement said.

Nearly 30 minutes after organizers suspended activities, dual lightning struck a maintenance area and a tree near the 16th tee and the driving range, Mark Russell, PGA's vice-president of rules, competition and administration, told reporters on Saturday.

The lightning knocked debris off the tree, wounding some people, he added.

Russell said organizers encouraged everybody to leave the course and take shelter. He also said the PGA had put a message on the scoreboards warning spectators that severe weather was approaching.

"You've got a lot of people, and you have to do that quickly and sometimes people don't take shelter," he said.

When asked whether a half-hour was enough time to safely evacuate the golf course, Russell said he couldn't really answer the question but said they had done everything they could.

"I wish I could say yes or no. I mean, we wanted to get the spectators, the players, the volunteers, everybody off here as soon as we possibly could, and the moment we saw we had danger, we suspended play. We had on the scoreboards that there was coming weather, and we got the players off, we got the volunteers off," he said.

All play was suspended for the day in the season-ending tournament in which Justin Thomas leads Rory McIlroy and Brooks Koepka. The tournament is expected to resume Sunday morning.