Experts say while the attacks aren't new, the concentration of them is. Elected officials on both sides of the aisle are concerned about the rise in violent attacks. Subscribe to ABC News on YouTube: https://abcnews.visitlink.me/59aJ1G ABC News Digital is your daily source of breaking national and world news, exclusive interviews and 24/7 live streaming coverage. Download the ABC News app for the latest headlines and alerts: https://abcnews.go.com/devices Watch 24/7 coverage of breaking news