The Boston Marathon, the longest-running major annual marathon in the world, has now been cancelled because of COVID-19 pandemic fears.

Boston mayor Marty Walsh said that the race, which had already been postponed to September 14 from its April slot, would not be held as planned for public health reasons.

"There's no way to hold the usual race format without bringing large numbers of people into close proximity," Walsh said in an announcement.

The marathon has been held every year without fail since 1897, generally drawing over 30,000 runners from all over the world.

Tom Grilk, chief executive of the Boston Athletics Association, which manages the Boston Marathon, said in a news release that "Our top priority continues to be safeguarding the health of the community, as well as our staff, participants, volunteers, spectators, and supporters."

The Boston Athletic Association said that entrants to the marathon could instead take part in a "virtual" Boston Marathon, anytime between September 7 to 14.

Entrants would need to complete the 26.2 mile distance within six hours and provide proof of timing, a statement said.

The 2021 Boston Marathon is scheduled for April 19.

Marathon racing around the world has faced severe disruption from the COVID-19 pandemic. The London Marathon has been postponed until October while the Tokyo Marathon took place with only a reduced field of elite runners.

The September 27 Berlin Marathon, another of the world's major marathon races, has also been cancelled.

The other two major marathons scheduled in the U.S. later this year -- the October 11 Chicago Marathon and the November 1 New York Marathon -- remain on the calendar.

Meanwhile, PGA Tour's John Deere Classic scheduled for July in Illinois, which was supposed to be the fifth event of the circuit's revamped schedule, has been cancelled due to state-related challenges regarding the COVID-19 pandemic. 

The tournament, which was also the first of the PGA Tour's revised schedule that could have potentially included fans, was due to be played July 9 to 12. 

The PGA Tour said it will fill the July week with a new tournament that will be determined in the near future. 

(With input from agencies)