London, England (Sports Network) - Amid all of the tragic news out from the Boston Marathon, runners will again take to the streets Sunday, this time for the 33rd running of the London Marathon. Half a million spectators and over 35,000 runners are expected to be in attendance.
The race will occur in the wake of Monday's two-bomb explosions near the finish line of the Boston Marathon. Three people were killed and at least 176 were injured in what is considered an act of terrorism.
"You look at what has occurred, if there are steps we can take to increase security and all sorts of measures one could deploy ...," London Marathon chief executive Nick Bitel told BBC Radio 5 Live.
"We run through the city," he added. "When you have an event of any nature, a marathon, parade, it's only as safe as the city itself. If it's not held in a stadium, you can't do a lockdown like you may do in a building."
The Kenyans have dominated the London race, including seven wins in the last eight years. Last year, Wilson Kipsang posted a winning time of 2:04.44, two minutes faster than countryman Martin Lei. Kipsang, a bronze medal winner at the London Olympics, just missed the course record last year by four seconds. He remains one of two men to eclipse the 2:05 mark for the marathon on three separate occasions.
Over his last six marathons, Kipsang has four wins and two thirds. His victory in 2011 in Frankfurt set a personal best of 2:03.42.
Among the notable runners participating in the race are Emmanuel Mutai, the London course record holder; 2012 London Olympic gold medalist Stephen Kiprotich; Patrick Makau, the current world record holder; Geoffrey Mutai, the current World Marathon majors champion; and Tsegaye Kebede, the 2012 Chicago Marathon winner.
Two-time champion Mary Keitany of Kenya is expected to be on hand to defend her title in the women's division. The field is loaded with quality runners, including Keitany's fellow countrymate Atsede Baysa, the double Paris marathon champion, and Aberu Kebede, the 2010 Berlin Champion.
Germany's Irino Mikitenko is also a two-time champion of the race, winning in back-to-back years - 2008-2009 - and poses as a major threat to Keitany and the rest of the field. Romania's Constantina Dita, a 42-year-old Olympic champion, will make her 10th London appearance.
Two of London's top female marathons have withdrawn from the race citing injuries. Freya Ross, who finished 12th last year, is nursing a troubled hip, while Helen Clitheroe is sidelined with an undisclosed illness.
Paula Radcliffe, a three-time champion in the event and the fastest female marathoner ever, also will be missing from the London Marathon. The 39-year- old Radcliffe has been limited in her training because of a foot injury and the birth of her second child.
The London Marathon also has been a paradise for Kenya as five different runners have won the race since 2005, with Martin Lel garnering three victories, including back-to-back scores beginning in 2007. The Kenya run was snapped in 2010 when Ethiopia's Tsegaye Kebede crushed Emmanuel Mutai by over a full minute.
Only two runners have won consecutive London Marathons in the race's 32 years, Martin Lel and Mexico's Dionicio Ceron, who strolled to victory three years in a row between 1994 and 1996. Given the lack of back-to-back victories, it might be difficult for Mutai to retain his title.
Winning back-to-back London Marathons has not been a problem for the women as compared to the men since they have accomplished the task eight times, with Germany's Katrin Dorre-Heinig doing it twice in a three-year span in the early 1990s. Irini Mikitenko, also from Germany, did it in 2008 and 2009, while Keitany has won the race the last two years.