Officials at Teodoro J. Schestakow Hospital said Tuesday that cyclist Sebastian Coue apparently crashed during the second stage of the rally and was exposed to temperatures above 40 degrees centigrade (104 Fahrenheit) before he was found.

Officials said it was unclear how long he had been exposed to the extreme heat.

The Dakar Rally, considered one of the most dangerous in motor sports, has already claimed three lives this year. Argentine bike rider Jorge Martinez Boero died in a crash in Sunday's first stage. On the same day, the pilot of an ultralight plane and his son died when the aircraft went down while following the race.

Meanwhile, defending bike champion Marc Coma of Spain won Monday's second stage of the Dakar Rally and also claimed the category lead after the 295-kilometer (185-mile) leg.

In cars, defending champion Nasser Al-Attiyah won the stage with Stephane Peterhansel of France taking the overall lead.

This year's edition of the rally, considered one of the most dangerous events in motor sports, has already claimed three lives.

Argentine bike rider Jorge Martinez Boero died in a crash in Sunday's first stage, and on the same day the pilot of an ultralight plane, and his son, died when the aircraft went down as it was following the race.

Rescue officials identified the dead as Luis Marcelo Soldavini, 37, and his son Tomas, 11.

Coma finished the special stage in 3 hours, 7 minutes, 21 seconds. He was 1:18 ahead of KTM teammate Cyril Despres of France and 2:33 ahead of Spanish rider Joan Barreda Bort.

In the overall standings, Coma was 2:30 ahead of Francisco Lopez of Chile and 2:52 in front of Despres.

"The start was very fast," Coma said. "Chaleco (Lopez) and me were riding at top speed. ... After that, arriving at the second part of the special with sand and dunes, it was a lot more technical with some navigation to do. I took the lead and kept riding at a good pace. I'm happy because I didn't get lost. So, it's been a good day for me." Al-Attiyah, driving a Hummer this year, finished the stage in 2:47:18. He was 54 seconds in front of Peterhansel in a Mini, and 2:42 ahead of Hummer teammate Robby Gordon of the United States.

In the overall, Peterhansel is 2:28 ahead of Gordon and 2:33 in front of first-day leader Krzysztof Holowczyc of Poland.

Al-Attiyah is in sixth place overall, 8:47 back.