Ukraine, Benghazi to lead Sunday shows

A new congressional probe into the State Department’s handling of the 2012 attack in Benghazi, Libya, and escalating unrest in Ukraine will likely dominate Sunday talk show news.

Pro-Russian separatists in eastern Ukraine insist that a controversial referendum set for Sunday declaring sovereignty over the region will happen. The referendum will likely take place in the Donetsk and Luhansk regions of eastern Ukraine, where armed groups have been involved in deadly clashes with Ukrainian security forces recently. Several Western powers have condemned the planned vote as illegitimate as well as the interim government in Kiev. 

Meanwhile, House Republicans are moving forward with a select committee to investigate the Benghazi attack that left four Americans dead, including U.S. Ambassador Christopher Stevens.

The abduction of more than 200 Nigerian schoolgirls this week by Islamist terrorist group Boko Haram will also be a topic of discussion.

Here's the lineup:

ABC's "This Week:" Defense Secretary Chuck HagelChuck HagelCreating a future for vets in DC Republicans back Clinton, but will she put them in Pentagon? There's still time for another third-party option MORE, Sen. Marco RubioMarco RubioPoll: Trump up by 2 points in Florida GOP vulnerables dial back Hillary attacks The Trail 2016: An important lesson in geography MORE, (R-Fla.), Rep. Adam Kinzinger, (R-Ill.)

NBC's "Meet the Press:" Pre-empted by coverage of Premier League soccer.

CBS' "Face the Nation:" Former Defense Secretary Robert Gates, House Intelligence Chairman Mike Rogers, (R-Mich.), Sen. Elizabeth WarrenElizabeth WarrenWarren’s power on the rise Helen Mirren gives advice for being a ‘nasty woman’ Warren slams GOP Sen. Burr as 'puppy on a leash' for backing Trump MORE, (D-Mass.)

CNN's "State of the Union:" Rep. Michele BachmannMichele BachmannThe right-wing wants a revolution, and we had better pay attention Bachmann: Trump, GOP feud isn't a 'civil war' Trump says 2016 is the GOP's last chance to win MORE, (R-Minn.), Rep. Debbie Wasserman Schultz, (D-Fla.), former senator Rick Santorum, (R-Penn.)

"Fox News Sunday:" Rep. Trey GowdyTrey GowdyLawmakers press Lynch for briefing on Yahoo secret email scanning reports Clinton IT aide pleads Fifth, skips hearing House Oversight subpoenas FBI for Clinton investigation documents MORE, (R-S.C.), Rep. Xavier BecerraXavier BecerraDems double down on Nevada Latino vote Clinton makes new push to win the House Dems bullish on Hispanic support, turnout MORE, (D-Calif.)

NPR’s “Weekend Edition Sunday:" Maria Korsnick, the first female chief nuclear officer in the U.S.; NPR’s Jeff Brady on the Keystone Pipeline project.