Sammy Wanjiru, a record-shattering Kenyan marathon runner and reigning Olympic champion, died May 15 in Nyahururu, a town about 115 miles north of Nairobi. He was 24.

The circumstances of his death remain murky, complicated by reports that he had multiple wives.

According to police, Mr. Wanjiru died after he fell from a balcony at his home. Some Kenyan officials said the runner committed suicide, but the Associated Press reported that a local policeman gave a different account.

Mr. Wanjiru’s wife Tereza Njeri reportedly found him in bed with another woman. Following an argument, Tereza locked her husband in the bedroom and ran away.

“He then jumped from the bedroom balcony,” police chief Jasper Ombati told the Associated Press. “In our estimation, we think he wanted to stop his wife from leaving the compound.”

By many accounts, the prodigious runner’s dramatic death prematurely ended what was blossoming into a historic career.

Kenyan Prime Minister Raila Odinga said recently that Mr. Wanjiru was “steadily developing into our country’s running phenomenon.”

Mr. Wanjiru, who was raised by a single mother and did not own a pair of shoes until he was a teenager, earned millions of dollars as a distance runner and consistently won big races. He was the youngest runner to win four major marathons.

Trim and muscular, he was known to set blazing paces throughout a race and then finish off his opponents with a devastating final burst of speed.

During the 2009 Chicago Marathon, he ran the fastest marathon ever on American soil when he finished in 2 hours 5 minutes 41 seconds. He also won the 2009 London Marathon in a personal best time of 2:5:10, and the 2010 Chicago Marathon.

In 2008, in his third marathon ever, he bested a 24-year-old Olympic record by three minutes on his way to the gold medal.

When he crossed the finish line at 2:6:32, many racing historians rated his as perhaps the finest marathon performance in history.

He was more than 2 minutes off the world record of 2:3:59, set in 2008 by Ethiopian Haile Gebrselassie, but the conditions that day in Beijing were brutal.

Under a cloudless sky, Mr. Wanjiru endured searing heat with temperatures peaking at 86 degrees to lead the last half-mile on his own.

“I had to push the pace to tire the other runners,” he said after the race. “I had to push the pace because my body gets tired when I slow down.”

Despite his country’s dominance in distance running, Mr. Wanjiru’s Olympic gold was the first awarded to a Kenyan in the marathon.

Samuel Kamau Wanjiru was born Nov. 10, 1986, in Nyahururu. He was raised on a farm and ran 12 miles to school and back every day.

He was recruited as a teenager by a Japanese athletic scout who was impressed that Mr. Wanjiru won a national cross-country race barefoot.

He spent his high school years in Sendai, the Japanese town ravaged by an earthquake in March, and ran competitively for a team sponsored by Toyota.

Mr. Wanjiru set a new world record for the half-marathon in 2005 and improved his time twice more before running full marathons. (Mr. Wanjiru’s half-marathon world record of 58:35 was beaten by Zersenay Tadese in March 2010 with a time of 58:23.)

In 2007, Mr. Wanjiru won the Fukuoka Marathon in his debut effort and set a course record. He finished second in the 2008 London Marathon before heading to Beijing.

Mr. Wanjiru’s last race was the 2010 Chicago Marathon. In December, he was arrested at his home after reportedly threatening to kill Tereza and their maid. He also was accused of wounding a security guard in the face with the shoulder stock of an illegally owned AK-47 rifle. Mr. Wanjiru, who denied the charges and said he was framed, was released on bail.

Besides Tereza, survivors include their two children. A complete list of survivors could not be determined. A Kenyan newspaper reported Mr. Wanjiru had at least two more wives and other children.

Despite his troubled personal life, Mr. Wanjiru was regarded in his profession as a future star. He often said he wanted to break the marathon world record and perhaps run a sub-two-hour race.

An Australian reporter in 2009 asked Mr. Wanjiru if he believed he could conclude his career as the greatest marathon runner in history.

“Yes,” he said. “I am still young. Everything is possible.”