By Staff

BOSTON (CBS) – Marcel Hug of Switzerland, the defending men’s wheelchair champion, pulled out of the Boston Marathon early Monday morning.

He made the announcement just hours before the start of the race, saying he will not return to defend his title. No reason was given for his withdrawal.

Hug is a five-time Boston champion and the course record-holder. He won the B.A.A. 5k race Saturday setting a new course record. Staff