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Chief Justice John Roberts, jurors sworn in as Trump impeachment trial opens
The impeachment trial of President Trump began in the Senate on Thursday as Chief Justice John Roberts and 99 of the 100 senators who will serve as jurors were sworn in. (Sen. Jim Inhofe, R-Okla., missed the session due to a family medical matter but is expected to return next week.)

The proceedings opened with a mixture of pageantry and partisan swipes that reflect the divide over the third impeachment of a president in U.S. history. House Sergeant-at-Arms Paul Irving led a procession of Democratic impeachment managers across the Capitol and the upper chamber formally received the articles of impeachment.

Trump faces two articles of impeachment -- abuse of power for allegedly pressuring Ukraine to investigate Democratic rival Joe Biden, using military aid to the country as leverage and obstruction of Congress in their investigation. Trump has repeatedly denied any wrongdoing and dismissed the impeachment trial Thursday as "totally partisan" and "a hoax."

Before the formal opening of the trial, the Government Accountability Office (GAO) issued a legal opinion saying Trump's administration broke the law by withholding defense aid to Ukraine.

Lawmakers are continuing to battle over whether new witnesses and evidence will be allowed at the Senate trial. Those issues aren’t expected to be decided until well after the trial begins in earnest. Senate Majority Leader Mitch McConnell, R-Ky., said the trial will continue at 1 p.m. ET Tuesday. Click here for more on our top story.

Other developments in Trump's impeachment:
- Hunter Biden will 'have to take one for the team' if Dems want witnesses in Senate impeachment trial: pundit
- Sen. Susan Collins hits back at 'mischaracterization and misunderstanding' of impeachment stance

U.S. soldiers clear rubble from a site of Iranian bombing at Ain al-Asad air base in Anbar, Iraq, Monday, Jan. 13, 2020. (AP Photo/Ali Abdul Hassan)

Iran rocket attack on Iraqi military base injured 11 US service members, official reveals
Eleven U.S. service members were injured in Iran's rocket attack targeting two Iraqi military bases last week in retaliation for the killing of top Iranian Gen. Qassem Soleimani, a spokesman for U.S. Central Command revealed Thursday night.

All of the injuries occurred at Al Assad Air Base, with the service members subsequently flown out and treated for concussion symptoms, the official said. President Trump and U.S. officials had said earlier that no Americans were killed or injured in the Jan. 8 attack. Meanwhile, Ayatollah Ali Khamenei, Iran’s supreme leader, addressed Friday prayers in Tehran for the first time since 2012 and used the platform to praise the country's retaliatory strikeClick here for more

Andrew Yang's wife reveals she was sexually assaulted by her doctor during first pregnancy
Evelyn Yang, wife of 2020 Democratic presidential hopeful Andrew Yang, opened up Thursday about a sexual assault she experienced while pregnant with the couple’s first child.

Yang revealed to CNN that she was a victim of her OB-GYN, Dr. Robert Hadden, in 2012. She said exams began as "routine" but changed after a few months. She told CNN's Dana Bash how exams became "longer" and "more frequent" as her pregnancy progressed, and she later realized the exams were "unnecessary.” Click here for more

James Comey focus of FBI leak investigation, report says.
Woman convicted in texting suicide case to be released early from prison. 
'Teacher of the Year' explains why she took a knee during anthem.

China's 2019 economic growth weakens amid trade war.
EXCLUSIVE: White House scrambling to roll out stimulus plan, tax cuts during 2020 race.
Walmart in hot water over Paul Walker car accident joke.
#TheFlashback: CLICK HERE to find out what happened on "This Day in History."

Mark Levin, host of "Life, Liberty & Levin," slams Democrats' hypocrisy and warns of Republican "weak links" in the battle over witnesses at Trump's impeachment trial in an appearance on "Hannity."

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Fox News First is compiled by Fox News' Bryan Robinson. Thank you for making us your first choice in the morning! Enjoy your day and weekend! We'll see you in your inbox first thing Monday morning.