An eyewitness has painted a vivid picture of the blasts that rocked the popular Boston Marathon in the US late yesterday (Nigerian time but about 2:50 p.m. Boston time), killing three persons and leaving at least 114 injured.

“I was there at the finish, shooting finish line scenes, and then, bang!, it just went off, and then less than 15 to 20 seconds after, there was a second explosion, closer to Fairfield Street,” said Boston.com’s Steve Silva.

“It was just an explosion. It came out of nowhere. ... I saw dismemberment. I saw blood everywhere,” he added.

Blood and broken glass covered sidewalks in the area after the blasts.

“There was blood everywhere; there were victims being carried out on stretchers. I saw someone lose their leg. People are crying. People are confused,” said Silva, who captured one of the explosions on video, said moments after the blasts.

There was instant chaos after two powerful explosions detonated in quick succession near the finish line in Boston’s Back Bay section.

“When the smoke cleared from what officials said may have been a terrorist attack, dozens of victims lay in the street, some unconscious, some grievously injured, including some whose limbs had been torn off by the blast,” reports Boston Globe.

The dead included an 8-year-old boy, according to two law enforcement sources briefed on the investigation. Boston Children’s Hospital reported that those treated there included a 9-year-old girl, a 7-year-old boy, a 12-year-old, and a 2-year-old, according to the report.

No arrests have yet been made but President Barack Obama has vowed that whoever planted the explosives would be found and brought to justice.

“We will find out who did this and we will hold them accountable,” Obama said in a statement last night.

•Photo, courtesy Boston Globe, shows an injured woman receiving assistance after the blasts.