BOSTON — The champion of the men’s 2013 Boston Marathon returned his medal to Mayor Thomas Menino to honor the city and those killed and injured in the bombings near the finish line of one of the world’s top running events.

Lelisa Desisa of Ethiopia participated in the Boston Athletic Association’s 10K race on Sunday and gave the marathon prize to honor the victims and Boston.

More than 6,400 athletes gathered on Boston Common. Most runners wore the blue and gold colors of the Boston Athletic Association, the nonprofit that organizes the annual marathon.

A moment of silence paid tribute to the bombing victims and the Massachusetts Institute of Technology police officer who was killed days after the marathon during a search for the suspects.