Two Lithuanian illusionists have reportedly set a new world record for holding their breath underwater, organizers said.

Brother and sister Arvydas and Diana Gaiciunas were chained on the bottom of a swimming pool at Druskininkai water amusement park in southern Lithuania on Saturday, in front of hundreds of onlookers.

Diana stayed under water for 11 minutes and 7 seconds. Arvydas held his breath for 15 minutes and 58 seconds, which organizers said broke the record set in 1959 by Canadian Robert Foster.

The pair were hospitalized for tests after the event and were said to be in stable condition.

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It was not clear whether officials from Guinness World Records or any other organization attended the event, nor if the attempt would be officially recognized.

"I know this is very dangerous, but we are trained for extreme stunts and we will have professional divers watching us," Arvydas Gaiciunas said before the performance.

The pair were chained to a metal frame and inhaled pure oxygen for 40 seconds before they were immersed in the water.

Lithuanian television showed the stunt live, with several underwater TV cameras.

The Gaiciunas siblings, both veteran circus performers, spent almost three days frozen in a 12-ton block of ice in 2005, for which the government rewarded them with 1,500 euros each.

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