Two bombings during the Boston Marathon on Monday, April 15 has caused the nation to mourn as it resulted in 3 deaths and over 100 injured spectators.

The Boston Marathon, which is a national tradition, attracts approximately half a million spectators and approximately 20,000 participants every year.

Of the 23,000 runners who began the race, only 17,600 crossed the finish line, as reported by the New York Times. The remaining 4,500 other participants were diverted from the 26.2 mile course due to the bombings.

The blasts were seconds apart and threw many runners off their feet as they neared the finish line on the North side of Boylston Street in Boston, Massachusetts.

According to Peter Fagenholtz, a trauma surgeon at Massachusetts General Hospital, some victims suffered shrapnel wounds and amputations and are in need of several operations.

The United State FBI have taken a lead in investigating the bombing and will have assistance from several other federal, state, and local law enforcement agencies.

As those who witnessed the explosions fled for safety, police officers secured the area as investigators checked each abandoned bag for a potential bomb.

During the interfaith service held at the Cathedral of the Holy Cross in Boston earlier today, President Obama gave an emotional speech and met with the families of victims at nearby hospitals. 

"As you learn to stand, and walk and run again. Of that I have no doubt," said President Obama. "You will run again. Because that's what the people of Boston are made of."

Obama commended Boston first responders for their diligent care and reaction to the explosion. He also promised to find those responsible for the tragic incident. 

"Yes, we will find you and yes you will face justice," he said. "We will find you and we will hold you accountable."

The victims of the explosions included 8-year-old Martin Richard, 29-year-old Krystal Campbell and Boston University graduate student 23 year old Lingzi Lu.