BEIJING — Samuel Wansiru pulled away over the final few miles Sunday to become the first Kenyan in the storied running history of that nation to win an Olympic marathon.

The 21-year-old negotiated the 26.2-mile (42.15-kilometer) course through the Beijing streets in bright morning sunshine in an Olympic record of 2 hours, 6 minutes, 32 seconds.

It was just the third marathon for Wansiru, also known as Wanjiru, who twice broke the world half-marathon record last year.

Two-time world champion Jaouad Gharib of Morocco won the silver in 2:07.16. Ethiopian Tsegay Kebede, winner of this year’s Paris Marathon, took the bronze in 2:10.00. Ethiopian Deriba Merga led much of the race but faded badly at the end to wind up fourth.

Wansiru won the Fukuoka International Marathon in Japan last December and was runner-up at the London Marathon in April.

The crowd roared as Wansiru entered the Bird’s Nest, and he responded by raising his left hand in acknowledgment, then clapped several times.

One lap later, just across the line, he kneeled and crossed himself several times. He had just broken the Olympic mark of 2:09.21 set by Carlos Lopes of Portugal in the 1984 Los Angeles Games.

As Wansiru was still on one knee, Gharib crossed the line for the silver.

Americans Dathan Ritzenhein and Ryan Hall finished ninth and 10th, respectively.

Temperature was 75 degrees (24 C) with 52 percent humidity when the race began at 7:30 a.m. and it heated up steadily through the morning, reaching 86 degrees (30 C) by the finish.

The lead pack began to separate through the first three miles (5 kilometers). By the halfway mark, eight were grouped at the front, led by Eritrean Yonas Kifle.

By the 18.6-mile (30-kilometer) mark, the pack had dwindled to three — Wansiru, Merga, and Gharib.

Reigning world champion Luke Kibet of Kenya stayed with the leaders through the early stages but fell back and finally pulled out of the race shortly past the halfway mark. He later said he had a stomach problem.

World record holder Haile Gebrselassie of Ethiopia decided not to run the race because of concerns about Beijing’s notorious air pollution. But after an overnight thunderstorm, a glorious blue sky greeted the final day of these games.

The race began at the edge of Tiananmen Square, then wound around the Temple of Heaven before turning northward toward the Olympic Green and the Bird’s Nest, where colorful dancers, drummers and cyclists entertained the crowd as it awaited the runners.