Police are working to establish the motive of a gunman who left three people dead at a family planning clinic in Colorado Springs on Friday.
The suspected gunman, Robert Lewis Dear, of North Carolina, was arrested.
Two civilians and a police officer died, and nine other people were injured, in the five-hour standoff at the Planned Parenthood clinic.
Lt Catherine Buckley said Colorado Springs Police did not know his “mentality, or his ideas or ideology”.
The Planned Parenthood group has drawn anti-abortion protests in the past.