Adventurer David Hempleman-Adams has won a top ballooning race in the US.

He and co-pilot Jon Mason finished ahead of the pack in the 16th America's Challenge Gas Balloon Race.

The pair made a fast descent at 35 knots to touch down at 8.30pm MDT (3.30am BST) near the Canadian border, about 64 miles (103km) north-west of Minot, North Dakota.

Organisers said unofficial results show that Hempleman-Adams and Mason flew 974 miles (1,568km) over nearly three days after setting off from Albuquerque, New Mexico.

The British team believe they have set a new America's Challenge race record time for being in the air by spending 71 hours and 32 minutes aloft - beating the old mark of 68 hours and 46 minutes, which was set in 2008.

This was the first America's Challenge win for Hempleman-Adams, from Wiltshire, and Mason, originally from Canterbury but who now lives in Queensland, Australia.

However, this was not their first win in a gas balloon race in Albuquerque, having won the international Gordon Bennett challenge in 2008.

A delighted Hempleman-Adams said: "We have wanted to win this balloon race since our Gordon Bennett win here in 2008.

"We were up against great competition from the top American Gas balloonists and the top German team with Wilhem Eimers, which has made it a really exciting race and the last 24 hours have been very tense.

"We are absolutely over the moon."

The rules of the race are simple, with the winner being the team that flies the furthest before landing.

Unlike hot air balloons, which can typically stay aloft for only a couple of hours, gas balloons use lighter-than-air gases such as helium and hydrogen and can stay airborne for 60 hours or more.

The balloons can be controlled only by releasing gas to go down and throwing out sand to go up.

For much of Monday and yesterday, Hempleman-Adams and Mason flew neck and neck with the race's defending champions, Peter Cuneo and Barbara Fricke of Albuquerque - and at one point they were only 0.6 miles (1km) apart.

The high-altitude duel spanned three states and nearly 24 hours as first one team and then the other took the lead.

Cuneo and Fricke landed about two hours before the Britons and finished only 46 miles (76km) behind.

Cuneo and Fricke have won the America's Challenge twice, in 2001 and 2010, and have finished second four times.

Hempleman-Adams and Mason were supported by team flight director Clive Bailey and weather expert Luc Trullemans, who together plotted the best route for the team.