Thailand's Nichol Tomas claimed the men's youth B title on the first day of boulder finals at the IFSC Youth World Championships in Arco in Italy ©IFSC/Twitter

Thailand's Nichol Tomas and France's Oriane Bertone claimed the respective men's and women's youth B titles on the first day of boulder finals at the International Federation of Sport Climbing Youth World Championships in Arco in Italy.

Tomas triumphed ahead of Japan's Junta Sekiguchi at the RockMaster Climbing Stadium.

After a difficult boulder problem, Sekiguchi was not able to find the summit of boulder four, making Tomas the champion.

Rounding off the podium was Latvia's Edvards Gruzitis.

In the women's youth B final, Bertone prevailed at the expense of Japan's Ryu Nakagawa.

The bronze medal went to Nakagawa's compatriot Hana Koike.

The men's junior boulder final saw Japan's Sohta Amagasa came out on top.

France's Leo Favot finished second, while fellow countryman Nathan Martin came third.

Following a rest day tomorrow, action in Arco continues on Friday (August 30).

Boulder semi-finals are scheduled in the men's and women's youth A events, and women's junior competition.