France’s counterterrorism prosecutor’s office has confirmed to NBC News that a man from the Gironde region was arrested today on terrorism charges.

The 18-year-old from southwest France was arrested at an undisclosed location while on vacation. Another 18-year-old was arrested in the southwestern Gironde region earlier this week.

Both men are suspected of planning a violent act, the prosecutor's office told NBC News. Investigators are yet to determine the seriousness of the threat and whether their plans went beyond messages that they had exchanged online.

French Interior Minister Gérald Darmanin has said Tuesday’s arrest may have involved plans to attack the 2024 Olympic Games.

Team USA's Olympic swimmers are getting in their final training sessions before their events get underway Saturday. But before they walk out to the poolside at the Paris La Defense Arena, they'll have to brave the ready room.

The ready room is where swimmers sit together and patiently await their races. Given that world-class athletes have spent four years training for the Paris Games, the mood is tense and Olympians are nervous with anticipation.

"Swimmers hate the ready room," explains Regan Smith, who won two silvers and a bronze at the Tokyo Games. "I think there are some oddballs out there who crave the ready room and love it. I’m not a huge fan of it ... [but] I’ve gotten much more confident as I've gotten older so it doesn't shake me quite like how it used to."

For others, it's a window into the minds of their rivals. Four-time gold-winner Ryan Murphy likes to listen to music and shut out any noise. "There’s definitely nervous energy in there and I think everyone has some different tendencies when they’re nervous," Murphy says. "You’re always gonna have the chatty person when they’re nervous [but] it isn’t me. You’re getting direct access to their brain."

Today marks the start of the women's soccer competition, with all 12 competing teams in action across the day. That includes the U.S. Women's National Team which faces Zambia in their opening group stage match in Nice at 3 p.m. ET.

The Olympics marks the start of a new era for the USWNT after an underwhelming performance at last year's World Cup in which the team suffered a Round of 16 exit to Sweden after penalties— its earliest ever elimination from the tournament.

The early exit in the World Cup saw former head coach Vlatko Andonovski resign and he has now been replaced by Emma Hayes, who turned Chelsea into a major force in women's soccer. Hayes has won 14 major trophies in her 12 years in charge in west London.

Even before he arrived in Paris, Australian BMX star Logan Martin's van was broken into in Brussels. In a post on Instagram, the passenger window of the Olympian's van appears completely smashed and Martin can be heard saying "luckily my bikes weren't in there although my bike bags were, with some things in there."

But Martin and his teammate then remembered that they had GPS tags in their bags and were able to locate them with most of their stolen goods. "Thank God for the bag tag. We found all our bags," Martin says in the video.

Anna Meares, Australia's chef de mission, later explained that thanks to the tags, the BMXer lost only his wallet in the end. Unfortunately, the thieves also feasted on Martin's chocolates, leaving the wrappers near the scene of the crime.

World No. 1 archer Casey Kaufhold, who is seeking to be the first American woman to medal since 1976, scored 672 in the ranking round and will enter the knockout stages as the No. 4 seed.

The score was close to par for the 20-year-old from Lancaster, Pennsylvania, with a current season average of 675 in 72-arrow play.

"To shoot something close to my average, I'm really happy," Kaufhold told reporters after the competition.

On this world stage, seedings going into knockouts don't matter much, Kaufhold said. "If you're number one shooting against number 64, that can still be a tough match. Anything can happen."

San Diego's Catalina GNoriega (ranked 648) and Boston's Jennifer Mucino (ranked 625) will enter the knockout stages from the Nos. 38 and 57 spots, respectively.

Korean archer Lim Sihyeon set a world and Olympic record, firing a 694 in a ranking round yesterday.

That 72-arrow score topped the previous all-time score of 692 set by Kang Chae-young in 2019 and the previous Olympic-best of 680 fired by An San in Tokyo.

Yesterday's scores don't count for medals, but establish seeding for the knockout competition that starts next Tuesday. The No. 2 seed will be fellow Korean Nam Suhyeon, whose 688 was a personal best and would have been an Olympic record.

Each competitor in the ranking round competes in 12 rounds of six-arrow ends, with scores totaled (60 maximum) after each of those dozen ends. When those 72 arrows have been shot, scores are tallied and competitors are ranked 1 through 64 for one-on-one knockout play.

Archery is being held at Esplanade des Invalides, a few arrows' shot from Napoleon's tomb.

The Catacombs of Paris hold millions of skeletons that are hidden 65 feet underground. NBC News’ Keir Simmons visits the Catacombs and talks to a historian about their history and significance.

French sprinter Sounkamba Sylla has been banned from the opening ceremony tomorrow because of a French secularism law that prohibits public sector workers from wearing a hijab.

"You are selected for the Olympics, organized in your country, but you can’t participate in the opening ceremony because you wear a headscarf," the 26-year-old member of the French 400-meter women's and mixed relay teams wrote on Instagram.

During the European Championships earlier this year, Sylla wore a blue cap that was incorporated into the team's kit. For the Paris Games, officials are trying to come up with a similar solution with the LVMH group, whose luxury brand Berluti is designing the uniform for the French delegation.

"We want to follow the same logic. That’s why we’re progressing in discussions with LVMH and Berluti," French Sports Minister Amélie Oudéa-Castéra said. "I am confident."

British tennis legend Andy Murray has withdrawn from the men’s Olympic singles, he said in a statement. The double Olympic gold medalist said that that he will still take part in the Olympic men’s doubles with fellow Team GB member Dan Evans.

“I’ve take the decision to withdraw from the singles to concentrate on the doubles with Dan. Our practice has been great and we’re playing well together,” Murray said in a statement today. “Really looking forward to getting started and representing GB one more time.”

The 37-year-old confirmed earlier this week that he will retire from professional tennis after the Paris Games following years of injury-related problems. The tennis player has particularly struggled for fitness in recent weeks in the wake of surgery to remove a spinal cyst.

Murray pulled out of the men’s singles tournament at Wimbledon earlier this month, but still played doubles alongside his brother Jamie Murray.