Know It All: Tuesday evening’s top stories from NBC News

'You hear people screaming, and running … lots of gun shots' 3:47

Here's a snapshot of some of the top stories we're following Tuesday evening:

American survivor recounts Kenyan siege horror

A chance table change during lunch may have led to an American woman surviving the horrific siege at a Kenyan mall over the weekend. Read more at NBC News.

Kenya's president says 5 suspects dead, 11 in custody after Nairobi mall siege

Kenya’s president Tuesday said security forces have killed five terrorists and arrested 11 suspects in connection with the horrific siege on a Nairobi shopping mall, bringing to a close four days of chaos and carnage. Read more at NBC News.

Rouhani: Iran not a threat, sanctions are 'violent'

Iranian President Hassan Rouhani told the United Nations General Assembly on Tuesday that his country poses "absolutely no threat to the world," and sanctions that have crippled its economy are "violent — pure and simple." Read more at NBC News.

Senate showdown: Cruz vows to argue against Obamacare until 'no longer able to stand'

Texas Sen. Ted Cruz took to the Senate floor just after 2:41 p.m. on Tuesday, vowing to speak in opposition to Obamacare “until [he] is no longer able to stand.” Read more at NBC News.

Report: Army set to implement partial tattoo ban

New U.S. Army recruits will not be permitted to sport tattoos below their elbows and knees or above their necklines, according to a new report from a military publication. Read more at NBC News

Another car submerged for decades may solve missing persons case in South Dakota

In an eerie echo of events earlier this month in Oklahoma, skeletal remains were discovered Tuesday in the car of two teenage girls who disappeared 42 years ago, a day after it was found wheels-up in a South Dakota creek, authorities said. Read more at NBC News. 

In first public letter since stepping down, ex-pope Benedict denies covering up child sex abuse

Printed in the La Repubblica newspaper, the Emeritus Pope's comments were a reaction to Italian author, mathematician and well-known atheist Piergiorgio Odifreddi's book about the problems facing the church. Read more at NBC News.