Brian Thompson

The man accused of fatally shooting UnitedHealthcare CEO Brian Thompson on a Manhattan street last week was found carrying a handwritten manifesto criticizing the U.S. healthcare system, New York police revealed Tuesday.

New York police released a new security camera picture Thursday of the man believed to have shot a top health insurance executive at close range in a brazen daylight murder outside a Manhattan hotel.

The latest picture, in which the suspect's face is uncovered and he is smiling or laughing, indicated progress in the manhunt after Wednesday's shock killing.