On the 15th of April, 2013, at 2:49 pm, two pressure cooker bombs exploded near the finish line of the Boston Marathon.
246 civilians were injured, and three killed.
What ensued was a manhunt for those responsible, unlike anything else in American history.
The 911 phone call that alerted police to the whereabouts of one of the perpetrators has, after more than three years, been released to the public.
Within hours of the attack, surveillance footage identified Chechen brothers Dzhokhar Tsarnaev and Tamerlan Tsarnaev as prime suspects.
The FBI swiftly released photographs of the two men. In the following days, the suspects killed a policeman and carjacked a civilian’s SUV. Three days later, the pair shot at police in a nearby town. An exchange of gunfire ensued, which resulted in the shooting of Tamerlan Tsarnaev. He died shortly after arriving at hospital.
Dzhokhar Tsarnaev escaped with the stolen SUV, running over his brother in the process.
Authorities asked that residents of Watertown, and surrounding areas including Boston, stay indoors. Public transport was shut down, as well as most businesses. Thousands of law enforcement officers combed through the neighbourhood, in an unprecedented manhunt.
Watertown resident David Henneberry contacted emergency services after discovering a bloodied man in his boat. The call led to the arrest and eventual conviction of Dzhokhar.
Dzhokhar was sentenced to death by lethal injection on the 24th of June, 2015.