 That's WBT's Mark Garrison reporting. Now, the gunman, 20-year-old Thomas Crooks, opened fire and was killed by a Secret Service sharpshooter. Today, a House committee will begin investigating what went wrong at the Trump rally. Now, it comes as the GOP convention starts today in Milwaukee. We still don't know who Trump has picked for his running mate, but he's expected to announce that today as well. And when he accepts the Republican nomination, the former president is expected to call for unity.