Boston, April 16 (IANS): "You heard boom-boom, then people screaming," said an eye-witness who recalled the horror of the twin Boston Marathon bombings that left three people dead and over 140 injured.

Oscar Otero was barely a few feet away from the blasts that took place Monday near the finishing line of the Boston Marathon.

"You heard boom-boom, then people screaming," Boston Globe quoted Otero as saying.

"There was blood all over the place. I saw a leg, people with bones sticking out of their skin," he said.

"It's hard to describe."

Al Ghilardi, a photographer for the Boston Athletic Association, was on the bridge over the finish line when he saw a red flash.

"Then a big plume of white smoke, and then I ducked because I felt the shrapnel," Ghilardi was quoted as saying.

"I saw people in awe. They were frozen. It took a few seconds for people to recognize what happened."

Andrea George, who was across the street from the finish line, recalled: "We heard a noise and heard the glass shatter."

"...I just started running. Everyone was running in different directions. It was the scariest thing I ever saw."

Mike Smith, a mechanic, said: "I was in shock. It was like a canon going off."

"I didn't know what was going on. I didn't realize what was happening until I saw people covered in blood. I saw maimed people."