Two British teams taking part in the Gordon Bennett 2010 international gas balloon race have been forced to land.
At about 0913 BST, Janet Folkes and Ann Rich were reported to have descended after flying 1037.74km (644.82 miles).
Colin Butter and Paul Spellward came down after flying 916.39km (569.42 miles).
Twenty teams launched their balloons near Bristol late on Saturday. The race aim is to see who can travel the farthest.
The remaining British team, David Hempleman-Adams and Simon Carey, are still flying and are lying in fifth position having flown 1214Km (754 miles) by 1913 BST on Monday.
The balloon is over the Mediterranean, south of France.
Mr Hempelman-Adams blogged at 2048 BST: "We're both tired now but at least it's not that cold because we're flying quite low. Simon's taking a kip while I fly.
"We've been told we can be no nearer than five nautical miles to Italian territorial land during the hours of darkness which counts as half an hour before sunrise and sunset. Tricky. We want to get this right and hope that the wind is on our side."
Swiss team Kurt Frieden and Pascal Witpraechtiger were in the lead on Monday evening, having flown 1868km (1160 miles) to put themselves just off the Montenegrin coast.
Balloons from Finland, Japan and Switzerland were the first to land.
The Swiss balloon came down in the Pyrenees and the other two landed on the west coast of France, just south of Bordeaux.
It is the first time in its 104-year history that the Coupe Aeronautique Gordon Bennett race has taken off from the UK.
Hempleman-Adams won the race in 2008 with co-pilot Jon Mason, giving them the right to host it in their home country.
Mr Hempleman-Adams and Mr Mason were the first UK team to win, flying 1,098 miles (1,767km) from Albuquerque in New Mexico to Lake Michigan in just over three days.
The balloons are controlled by releasing gas to descend and throwing out sand to ascend.
The Duke of Edinburgh and Sir Richard Branson are patrons of the 54th Coupe Aeronautique Gordon Bennett race.
The race was founded by Victorian newspaper tycoon James Gordon Bennett whose eccentric behaviour gave rise to the eponymous expression of incredulity.