'Start Here' podcast: Temperature rising

Scott Pruitt remains on thin ice with President Trump.

It's Wednesday, April 4, 2018. Here are some of the stories we're talking about on ABC News' new daily podcast, "Start Here."

1. Pressing Pruitt

EPA Administrator Scott Pruitt was already controversial in environmental circles. But right now, it's Pruitt's activities outside his office that reportedly have President Donald Trump weighing his next firing. ABC’s John Santucci says despite enacting the president’s policies, Pruitt may be too problematic for Trump to keep on.

2. Major moment for Mueller

Five people have pleaded guilty so far in Special Counsel Robert Mueller's Russia investigation. Yesterday, Dutch lawyer Alex van der Zwaan became the first to be sentenced in the probe. ABC News correspondent Aaron Katersky tells us why this is a significant development.

3. Social media scares during YouTube shooting

You might have seen the aerial shots yesterday. YouTube's pristine headquarters, littered with police cars, were evacuated. Employees were patted down one by one as they left. All after a shooting that appeared to take place in a courtyard.

As one social media company dealt with an active-shooter situation, former FBI Special Agent and ABC News contributor Steve Gomez says another Silicon Valley giant was trying to figure out how not to make it worse.

4. Migrants on the move in Mexico

You might have heard about this so-called "caravan" of people moving from Honduras, through Mexico, and up toward the U.S. border -- hoping to be accepted as asylum-seekers.

We speak to Daniel Carranza, who is covering this story for ABC News in Oaxaca and says the group is on the move, but some of the migrants actually hope to stay in Mexico.

5. Martin Luther King Jr.'s legacy 50 years later

It was April 4, 1968, and Dr. Martin Luther King Jr. was in Memphis, Tennessee, to support striking sanitation workers. He was relaxing on the balcony of the Lorraine Motel in the early evening when he was struck by a single bullet, fired from a Remington rifle across the street. King was pronounced dead an hour later.

We speak to ABC News "Nightline" co-anchor Byron Pitts about what effect King would have had on today's young activists.

"Start Here" is a daily ABC News podcast hosted by Brad Mielke featuring original reporting on stories that are driving the national conversation. Listen for free at Apple Podcasts – also available on TuneIn, Spotify, Stitcher, Google Play Music, iHeartRadio and the ABC News app.

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