Net closes in on university duo Andrew Warren and Wyndham Lathem after fatal stabbing in Chicago
The attack, which was described as "domestic", was so violent that the knife used was found broken.
Friday 4 August 2017 10:51, UK
Police say they are closing in on two university employees wanted after a 26-year-old American man was found stabbed to death in Chicago.
Oxford University's Andrew Warren, 56, and Northwestern University professor Wyndham Lathem, 42, are suspected of in Lathem's flat on 27 July.
Chicago police spokesman Anthony Guglielmi said the hunt had "intensified and narrowed".
Investigators think they know where the men are or are heading, and Mr Guglielmi urged them to surrender.
Warren, a former coach driver from Swindon, Wiltshire, was visiting America for the first time.
It is not yet known how he knew Lathem, or if he knew the victim before travelling from the UK to Chicago.
As senior treasury assistant he was in charge of pensions and payroll at the University of Oxford's Somerville College, but has now had his name and photograph removed from the college's online directory.
While it is know that Lathem was friends with Mr Cornell-Duranleau on Facebook, the nature of their friendship is not yet clear.
The respected professor - who specialised in the bacteria that caused the bubonic plague - has now been placed on leave from Northwestern University and banned from entering the campus.
Mr Cornell-Duranleau's mother said the family does not know the suspects and requested time "to process and grieve this tragedy privately".
Police have described the attack - which caused death by multiple sharp force injuries - as "domestic in nature" but are yet to establish a motive for the killing.
A spokesman for Chicago police said the attack was so violent that the blade of the knife believed to have been used was broken.
A former employer described Mr Cornell-Duranleau as a "great kid", adding "he wanted to be something so bad, though I don't know what that was or if he ever found his niche in life."