Trump shooter purchased ammunition just prior to rally assassination attempt: Source

The gunman at former President Trump's rally purchased ammunition shortly before he attempted the assassination on Saturday, according to a federal law enforcement source briefed on the matter.

Thomas Matthew Crooks has been identified as the shooter, and it is unclear how much ammunition he purchased prior to the rally. Crooks fired on Trump with a rifle several times before being killed by Secret Service counter snipers.

Crooks' volley struck Trump in his right ear as well as three other people in the crowd. One of the crowd members was instantly killed, and two others were critically injured. Corey Comperatore was killed shielding his wife and daughters. The the others who were injured have not been identified.

Trump recovered from the incident quickly and has stuck with plans to move forward with the Republican National Convention this week in Milwaukee, Wisconsin. He is expected to announce his running mate selection later Monday.