Boston, MA (Sports Network) - Police say at least three people have been killed in the explosions near the finish line of the Boston Marathon.
The two blasts marred Patriots' Day in Boston, transforming a celebratory atmosphere during one of the most prestigious races into a chaotic scene.
Police commissioner Edward Davis confirmed at a news conference that, at 2:50 p.m. ET, there were simultaneous explosions along the route of the Boston Marathon. "These explosions occurred 50 to 100 yards apart and each scene resulted in multiple casualties," Davis said.
The Boston Globe is reporting that at least 125 people were injured and a person of interest in connection with the bombing was being questioned by authorities.
According to The Wall Street Journal, officials found what they believe to be five additional, undetonated explosive devices around the Boston area.
President Barack Obama addressed a concerned nation during a news conference at 6:10.
"We don't yet have all the answers. ... We still do not know who did this or why," Obama said. "But make no mistake: We will get to the bottom of (this). We will find out who did this. We will find out why they did this. ... Any responsible groups will feel the full weight of justice."
Police initially reported a third explosion at the JFK Library, then said it had been a fire.
Davis urged people to stay calm and understand that this is an ongoing event.
Fearing more explosions, authorities have told people to stay inside and avoid large crowds.
The top runners in the marathon had finished just past Noon.
Lelisa Desisa of Ethiopia captured the Boston Marathon, while Kenya's Rita Jeptoo claimed the women's title for a second time.
Desisa finished in a time of 2 hours, 10 minutes and 22 seconds to break Kenya's string of three straight Boston champions. He became the fourth Ethiopian winner and first since Deriba Merga in 2009. Hailu Negussie in 2005 and Abebe Mekonnen in 1989 were the other Boston winners from Ethiopia.
Kenya's Micah Kogo finished second, just five seconds behind, followed by Ethiopia's Gebregziabher Gebremariam at 2:10.28 and American Jason Hartmann at 2:12.12. Hartmann also finished fourth last year.
Defending men's champ Wesley Korir of Kenya was fifth, finishing at 2:12.30.
Jeptoo crossed the finish line first for the women in a time of 2:26.25 for her second Boston Marathon win. She also won in 2006 and became the third straight Kenyan to win the women's crown.
Ethiopia's Meseret Hailu finished second at 2:26.58 and 2012 champion Sharon Cherop was next at 2:27.01.
A Kenyan woman has claimed the title 10 times in the last 14 years.
American Shalane Flanagan was fourth, followed by Tirfi Tsegaye of Ethiopia and American Kara Goucher.
04/15 22:07:30 ET