NEV. SHOOTER GOT GUN FROM HOME

SPARKS, Nev. (AP) -- The 12-year-old student who opened fire on a Nevada middle school campus, wounding two classmates and killing a teacher before he turned the gun on himself, got the weapon from his home, authorities said Tuesday.

Washoe County School District police said they are still working to determine how the boy obtained the 9mm semi-automatic Ruger handgun used in the Monday morning spree at Sparks Middle School. The boy's parents are cooperating with authorities and could face charges in the case, police said.

Authorities say they're withholding the seventh-grader's name out of respect for his family.

At a news conference Tuesday, law enforcement and school officials again lauded the actions of 45-year-old math teacher and former Marine Michael Landsberry, who tried to stop the rampage before he was killed.

"I cannot express enough appreciation for Mr. Landsberry," Washoe County School District Superintendent Pedro Martinez said. "He truly is a hero."

NUKE OFFICERS LEFT BLAST DOOR OPEN

WASHINGTON (AP) -- Twice this year alone, Air Force officers entrusted with the launch keys to nuclear-tipped missiles have been caught leaving open a blast door that is intended to help prevent a terrorist or other intruder from entering their underground command post, Air Force officials have told The Associated Press.

The blast doors are never to be left open if one of the crew members inside is asleep - as was the case in both these instances - out of concern for the damage an intruder could cause, including the compromising of secret launch codes.

Transgressions such as this are rarely revealed publicly. But officials with direct knowledge of Air Force intercontinental ballistic missile operations told the AP that such violations have happened, undetected, many more times than in the cases of the two launch crew commanders and two deputy commanders who were given administrative punishments this year.

The blast door violations are another sign of serious trouble in the handling of the nation's nuclear arsenal. The AP has discovered a series of problems within the ICBM force, including a failed safety inspection, the temporary sidelining of launch officers deemed unfit for duty and the abrupt firing last week of the two-star general in charge. The problems, including low morale, underscore the challenges of keeping safe such a deadly force that is constantly on alert but is unlikely ever to be used.

The crews who operate the missiles are trained to follow rules without fail, including the prohibition against having the blast door open when only one crew member is awake, because the costs of a mistake are so high.

APPLE UNVEILS NEW MACS, IPAD AHEAD OF HOLIDAYS

SAN FRANCISCO (AP) -- Apple Inc. is refreshing its iPad lineup and slashing the price of its Mac computers ahead of the holiday shopping season, as it faces an eroding tablet market share and growing competition from rival gadget makers.

Apple unveiled a new, thinner, lighter tablet called the "iPad Air" along with a slew of new Macs Tuesday at an event in San Francisco. The iPad Air weighs just 1 pound, compared with 1.4 pounds for the previous version. Apple marketing chief Phil Schiller called the tablet a "screaming fast iPad." He said it is eight times faster than the original iPad that came out in 2010.

The iPad Air will go on sale Nov. 1 and start at $499 for a model with 16 gigabytes of memory. Apple plans to phase out its third and fourth generation iPads while the iPad 2, which launched in 2011, continues selling at $399. A new iPad Mini, meanwhile, will be available later in November starting at $399 for a 16-gigabyte model. It has a retina display designed to give it a clearer, sharper picture and the same 64-bit chip that powers the iPad Air.

The iPad's market share has been eroding compared with cheaper rivals running Google Inc.'s Android operating system. Research firm Gartner Inc. estimates that Android tablets will end 2013 with a 50 percent share of the worldwide market versus 49 percent for the iPad. Just two years ago, the iPad commanded a 65 percent market share compared to 30 percent for Android tablets.