Bombers: Autopsy results show that Tamarlan Tsarnaev died of gunshot wounds and blunt force trauma to his head and torso the night of a shootout with police in Watertown, Mass. Tsarnaev was hit by police gunfire and run over by the hijacked SUV his brother drove to get away. Authorities have found explosive residue on the kitchen table in his home, suggesting that he built bombs in the house with his wife and infant present. But CBS News reports that the female DNA and fingerprint found on bomb fragments do not match the wife, Katherine Russell.

World: Five American soldiers were killed by a bomb in southern Afghanistan. A total of 19 Americans died this week in the bombing and three air crashes.

>The death toll in the Bangladesh factory building collapse has reach 517 and is now the worst garment factory disaster ever. The 1911 Triangle Shirtwaist Company fire in New York, which killed 146 workers, was followed by labor and factory reform.

The Big Burn: A wildfire burning in Ventura County up the coast from Los Angeles has grown to 30,000 acres. Some homes have been damaged but none have burned.

Taking Bets: Jockey Kevin Krigger today is a contender to become the first black jockey to win the Kentucky Derby since 1902. Krigger wlll be riding Goldencents, one of the favored horses. Black jockeys once dominated American horse racing, first as slaves, but when racing became lucrative the black jockeys were squeezed out. Krigger needs to watch out for Rosie Napravnik, a veteran jockey aiming to become the first woman to win the Derby.

Wings: The Solar Impulse finished the first leg of its cross country flight, landing in Phoenix this morning. The plane is powered by 12,000 photovoltaic cells and travels at about 45 mph.

First Class: The Navy is moving ahead with plans to build a new fleet of presidential helicopters. Similar plans were cancelled in 2009 when the projected cost ballooned to $13 billion. So far, there’s no total cost figure for the new helicopters.

Shoot: As many as 70,000 NRA members are at their annual convention this weekend in Houston celebrating the defeat of the gun bill. The theme is “Stand and Fight”, like it’s a prom with guns. Speakers include such gun-loving luminaries as Texas Sen. Ted Cruz, Louisiana Gov. Bobby Jindal, former Pennsylvania Sen. Rick Santorum, and Texas Gov. Rick Perry, plus one more but Rick Perry forgot his name.

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