BOSTON (AP) -- Jurors in the Boston Marathon bombing trial spent the first day of testimony listening to heartbreaking stories from victims and watching graphic videos of blown-off limbs, bloody sidewalks and chaos after the 2013 attack.

In this courtroom sketch, U.S. Attorney William Weinreb, left, is depicted delivering opening statements in front of U.S. District Judge George O'Toole Jr., right rear, on the first day of the federal death penalty trial of Boston Marathon bombing suspect Dzhokhar Tsarnaev in Boston (AP Photo/Jane Flavell Collins)

Prosecutors on Wednesday asked three women who were severely injured to describe their memories of the bombing, their wounds and the terror they felt in the moments after the blast.

One of them, Karen Rand McWatters, described holding the hand of her friend, Krystle Campbell, as Campbell died on the pavement. McWatters lost her left leg.

A lawyer for Dzhokhar Tsarnaev bluntly told the jury that her client committed the crime, but said he fell under the influence of his now-dead older brother, Tamelan. The defense said Tamerlan was the mastermind.

Testimony resumes Thursday.

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