'Start Here': John Bolton's book fallout and Kobe Bryant helicopter investigation

Here's what you need to know to start your day.

It's Tuesday, Jan. 28, 2020. Let's start here.

1. Bombshell book

In the unpublished manuscript of "The Room Where It Happened" reported by the New York Times, Bolton claims President Donald Trump told him that aid to Ukraine was tied to investigations into former Vice President Joe Biden.

Trump told reporters on Monday, "I haven't seen a manuscript, but I can tell you that nothing was ever said to John Bolton."

The revelations caused "confusion" and "frustration" among Senate Republicans, some of whom were blindsided by the news as moderates weighed whether they should hear from Bolton during the trial, says to ABC News Senior Congressional Correspondent Mary Bruce: "This makes them think that they do need additional information and that they are a lot more open to calling witnesses now after getting a glimpse of what Bolton might testify to."

2. Helicopter crash investigation

"It's unclear exactly what the pilot did, but we can tell by the data that has come in that even though he had followed this highway quite awhile, all of a sudden he turned left and started trying to climb and ran into the hillside," ABC News Senior Transportation Correspondent David Kerley says. "According to the NTSB, which was on the scene yesterday, they found part of the wreckage on one side of the hill and part of the wreckage on the other side of that."

3. 'Zero cooperation'

Federal prosecutors in New York have accused Prince Andrew of providing "zero cooperation" in their ongoing criminal investigation into sex trafficking by Jeffrey Epstein's co-conspirators.

The embattled prince publicly offered to cooperate with law enforcement in an interview with the BBC in 2019 after facing renewed attention to sexual assault allegations against him linked to the case, but he has yet to respond to a request for an interview from federal prosecutors and the FBI, according to U.S. Attorney Geoffrey Berman.

Buckingham Palace declined to comment and referred inquiries to Prince Andrew's legal team. Prince Andrew, who stepped back from his royal duties last year, has denied both the allegations against him and knowing or suspecting that Epstein was abusing underage girls.

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Elsewhere:

'$500,000 worth of jewelry': Former Philadelphia 76ers superstar Allen Iverson has reportedly had an estimated half a million dollars of jewelry belonging to him stolen from a Philadelphia hotel.

'Human-to-human transmission': The U.S. has now confirmed five cases of the coronavirus in U.S. patients. Two patients are located in California. Chicago, Washington state and Arizona have each reported one coronavirus case.

'Moral responsibility': Hundreds of Amazon employees are taking a stand against what they say is the e-commerce giant's "insufficient action on the climate crisis," in spite of claims that their jobs were threatened for speaking out in the past about the issue.

'Acted with heroism': In a dramatic scene caught on camera, good Samaritans acted swiftly to help a woman stuck under an SUV in Manhattan on Sunday. She was reportedly knocked down in a traffic accident.

From our friends at FiveThirtyEight:

'Will the Bolton news force Republicans to call witnesses in the impeachment trial?': Bolton’s version of events undermined the president’s claim, which has been an important part of his defense during the impeachment process, that the decision to freeze aid to Ukraine was independent from requests that Ukraine investigate the Bidens.

Doff your cap:

Los Angeles Lakers star LeBron James shared a heartfelt tribute to his "brother" and former Olympic teammate Kobe Bryant on Monday, promising to carry on the NBA superstar's legacy in the wake of his untimely death.

"I’m Not Ready but here I go. Man I sitting here trying to write something for this post but every time I try I begin crying again just thinking about you, niece Gigi and the friendship/bond/brotherhood we had," James wrote on Instagram. "I literally just heard your voice Sunday morning before I left Philly to head back to LA. Didn’t think for one bit in a million years that would be the last conversation we’d have."

James shared the post to his nearly 60 million Instagram followers late Monday night. It acquired about 4 million likes in less than an hour.

Bryant was not a frequent Instagram poster, but his last post before his death featured an image of he and LeBron smiling and embracing each other on the court.