A Canterbury commerce graduate has been caught up in the police investigation into the killing of UnitedHealthcare chief executive Brian Thompson

RNZ reports that Niki Dilley, who'd been visiting New York, has described the police investigation at his hostel - where the chief suspect was also staying - as "scary but cool".

It comes as detectives investigating the killing of Thompson recovered possible DNA evidence from items found at the scene, according to a senior law enforcement official briefed on the investigation.