6:18 p.m. ET: President Obama signed the Honoring America's Veterans and Caring for Camp Lejeune Families Act of 2012 into law on Monday.

The bill promises health benefits for Marines and families who were exposed to contaminated water at a North Carolina Marine base for decades. "Nightline's" investigation into the water contamination at Camp Lejeune revealed some startling stories. Watch it HERE:

5:22 p.m. ET: Gabby Douglas won loud cheers as she prepared to take the beam today, but her performance ended her Olympics debut on a sour note. video platform video management video solutions video player

From the beginning, the U.S. gymnast was wobbly in the women's beam final. A fall off the beam sank her hopes of a medal, but her performance was marked by near-falls throughout. While Aly Raisman, the team captain who surprising lost out on a bronze medal in the all-around final, redeemed herself, scoring bronze with her balance beam routine.

3:49 p.m. ET: BREAKING: Jared Lee Loughner pleaded guilty Tuesday to going on a shooting rampage at a political gathering, killing six people and wounding 13 others, including his intended target, then-Congresswoman Gabrielle Giffords.

Pima County Sheriff's Department

Read the full story, including Giffords' statement, HERE

1:12 p.m. ET: Heartbreak in China as track star Liu Xiang failed to finish a single race to qualify past the first heat of the 110-meter hurdles.

Credit: Daniel Ochoa De Olza/AP Photo

Read the full story HERE and watch "Nightline" anchor Bill Weir's Olympic recap HERE:

11:48 a.m. ET: Oscar, Grammy, Tony and Pulitzer Prize-winning composer and conductor Marvin Hamlisch, who composed dozens of classics including "The Way We Were," has died. He was 68.

Read more about his work HERE and tune into "Nightline" tonight as we pay tribute to the conductor.

Credit: Christy Bowe/Corbis

10: 50 a.m. ET: The best city for the United States to host the 2024 summer games is… Milwaukee??

That's what the Wall Street Journel is saying. They compared sport-crazed towns with big TV markets to come up with their recommendation. Read the full story HERE.

Wisconsin native and "Nightline" anchor Bill Weir was pretty stoked about the idea, tweeting:

9:55 a.m. ET: EXCLUSIVE: The psychiatrist who treated suspected movie-theater shooter James Holmes made contact with a University of Colorado police officer to express concerns about her patient's behavior several weeks before Holmes' alleged rampage, sources told ABC News.

Read the full story HERE

Credit: ABC