BOMBING AT BOSTON MARATHON-GRAPHIC PHOTOS

[Duchess]

The two bombs that killed three people and injured at least 176 at the Boston Marathon on Monday were made from six-liter pressure cookers crammed with shards of metal, nails and ball bearings and stashed in black backpacks, police sources revealed today.

The cruelly-designed bombs have 'frequently' been used in Afghanistan, India, Nepal and Pakistan, according to a 2010 Homeland Security Department pamphlet - hinting at the origins of the bombers behind the worst terrorist atrocity in the U.S. since 9/11.

When the devices exploded near the crowded Boston Marathon finish line around 2.50pm on Monday, victims suffered as many as 40 shrapnel wounds each and at least 10 people needed amputations. Witnesses described seeing body parts flying through the air and shoes that 'still had flesh in them'.

Sources added to CNN that a timer was likely used to activate one of the bombs. They are believed to have contained black powder or gunpowder as the explosive, and information on how to make such a bomb is available on the internet, experts said.

Although no group has yet claimed responsibility for the attacks, similar devices were used in the failed 2010 attempt to bomb Times Square by Faisal Shahzad, who admitted he had undergone bomb-making training at a militant Islamist faction camp in Pakistan.

A pressure-cooker bomb is also a preferred weapon of al-Qaeda and listed as the 'most effective' weapon of jihad, according to an English-language terror magazine called Inspire.

Another article in Inspire last year listed 'the most important enemy targets' for jihadists in America - and included sporting events, CNSNews noted.

This is Martin & his family, he was killed and his little sister lost a leg. Their Dad was running yesterday.



...and this is Krystle, she died too.