5 things you need to know Tuesday

Apple expected to unveil next iPhone

Apple has made it official. The company is holding a media event at its Cupertino, Calif., corporate campus today, presumably to introduce a new iPhone. Industry experts suggest the new iPhone will support fingerprint authentication, while a low-cost version of the device will be available in China and other developing nations. Apple is also expected to unveil more details of iOS 7, the latest upgrade of the mobile operating system that runs the iPhone and iPad. It will sport a completely different look as well as changes to basic functions such as navigating e-mail.

Obama sees possible breakthrough on Syria

President Obama said he would "run to ground" a proposal floated by the Russians that would wrest control of chemical weapons from Syria and would potentially head off a U.S. military strike against the Bashar Assad regime. Obama said he would "absolutely" put off a punitive strike if Assad gave up his chemical weapons. Senate Majority Leader Harry Reid, D-Nev., delayed a procedural vote on military action in Syria that had been scheduled for Wednesday in order to buy the president more time to make his case to senators and to the public.

George Zimmerman detained after 911 call from wife

Police in Lake Mary, Fla., held George Zimmerman in "investigative detention" after a 911 call from his estranged wife who reported that he punched her father in the nose and threatened them both with a gun. In an audio recording of Shellie Zimmerman's 911 call to police, she said Zimmerman smashed an iPad she was holding and cut it with a pocket knife, struck her father in the nose and threatened both while putting a hand on a gun. George Zimmerman was later released.

NASCAR levels historic penalties after spinout at Richmond

NASCAR put Ryan Newman into the Chase for the Sprint Cup and removed Martin Truex Jr. after ruling Michael Waltrip Racing "attempted to manipulate" the outcome of Saturday's race at Richmond, Va.

NYC voters go to polls in first round of mayor's race

In advance of today's New York City mayoral primaries, a pair of final polls showed public advocate Bill de Blasio may have enough support among Democrats to advance to the Nov. 5 general election. De Blasio had double-digit leads among likely Democratic voters over former comptroller Bill Thompson and City Council Speaker Christine Quinn in both the Quinnipiac Poll and a survey by NBC News 4/Wall Street Journal/Marist Institute of Public Opinion released Monday.