Authorities have no motive for a mass murder by a soldier at America's largest military base; Rihanna tells what started the violent argument between her and Chris Brown, and discusses the frightening look in his eyes.  Details on today's KISS News Now!

• The death toll is at 13 this morning after a shooting rampage at Fort Hood in Texas.  The suspected shooter is unconscious and in stable condition on a ventilator.  Army psychiatrist Major Nidal Malik Hasan was shot four times; his motive for the shootings isn't clear, but he was set to deploy soon and had argued with fellow soldiers who supported the wars in Iraq and Afghanistan.  The 39-year-old officer reportedly had been hassled by some because he was of Jordanian descent; investigators started looking at Dr. Hasan also discussed suicide bombings and other threats on the Internet.  The victims were shot at a center where soldiers undergo medical screening before deploying to or returning from combat overseas. 
  
  The base commander says according to witnesses, Hasan--a lifelong Muslim, according to his cousin--shouted, "Allahu Akbar!" ("God is great!" in Arabic) before opening fire calmly.  Thirty people are wounded.
  
   
• Rihanna opens up more about the night Chris Brown beat her up.  She tells ABC's Diane Sawyer she confronted him over a message from a girl on his cell phone.
  
  "I couldn't take that he kept lying to me, and he couldn't take that I wouldn't drop it," she says.  Their argument in the rental Lamborghini until he began to bite and punch her as he drove, and her mouth filled with blood.  She had but one thought in that moment, she recalls:  "When is it going to stop?  When is it going to stop?  He had no...no soul in his eyes.  Just blank.  He was clearly blacked out."
  
  Tonight on 20/20 on Channel 2, Rihanna discusses how she finally broke it off with the best friend with whom she was deeply in love.
  
  
  
  
   
• A four-year-old boy fights for life at Children's Healthcare at Egleston, after he was hit by a CSX train.  Elijah Anderson was running after the family dog when he followed the pet right onto the tracks.  The engineer wasn't able to stop in time and hit the boy at about 30 mph.  But he survived, and this morning, little Elijah's condition has been upgraded to stable.
  
  
• Third place finisher in the Atlanta mayor's race, Lisa Borders, says she's not yet ready to offer an endorsement for either candidate in the runoff.  She met Thursday with Kasim Reed, and will talk to Mary Norwood today.
  
  Charges are piling up against the owner of that wrecked Morehouse charter bus.  Already accused violating the law by continuing to ride without proper licensing or insurance, 38-year-old Stephen McClardy is also facing two charges of writing bad checks.  Police say when he bonds out of Fulton County, he has charges waiting for him in Gwinnett.  Thirteen Morehouse band members were hurt in last Saturday's bus wreck.
  
  
• Athens-Clarke County Police are wrapping up the investigation into a murder-suicide that started with a woman's  body found in a parked car about a mile from the UGA campus.  Police say 25-year-old Michael Wise killed 20-year-old Kendra Borders, the mother of his three children, then shot himself in the passenger seat when cops pulled over the car in which he was a passenger. No motive is known.
  
  
• In KISS news about your health:  fat is linked to 100,000 new cases of cancer this year.  Researchers for the first time have put numbers on your chances of getting cancer from being overweight:  49% of endometrial cancers are believed to be linked to obesity; 35% of esophageal cancer and 24% of kidney cancers.
  
  
• The American Medical Association and AARP are now backing current health insurance reform legislation on Capitol Hill.  Thousands of conservatives rallied on the Capitol yesterday, hollering to "kill the bill."
  
  
• President Barack Obama is set to sign a bill extending jobless benefits 20 weeks and prolonging the $8,000 homebuyer tax credit.  The law also aims to spur job creation by giving an additional tax credit boost to struggling businesses.
  
  
• The parents of a Spelman College sophomore killed by a stray bullet as she walked on the Clark Atlanta University campus go through with their plans to sue Clark for Jasmine Lynn's death.  The lawsuit seeks an unspecified amount of money.  Lynn's mother, Constance Franklin, said Thursday, "No amount of money could heal my pain.  I don't want another parent to have to stand here in my shoes.''  Lynn was gunned down on a sidewalk when a fight broke out nearby and shots were fired.  The gunman indicted in the killing says he is not the shooter--a friend of his is.
  
  
• The KISS 104.1 weather forecast:  sunny blue skies and a high of 66, tonight's lows 36-42.