The body of the 25 year old was discovered in the area of Bank Place in Derry at around 10.20pm on Sunday evening.
Results of yesterday's post-mortem have led them to believe his death was not the cause of foul play.
They are investigating at some stage before his death, his wallet had been stolen which was recovered in a bin nearby.
Police believe the wallet being stolen is a seperate incident to Connall's death.
Cheif Inspector Tony Callaghan made this appeal on today's Shaun Doherty Show: