A suspended Dalhousie University medical student who allegedly told his psychiatrist he had thoughts of shooting up to 20 people, faces a new charge — sexual assault.

Stephen Gregory Tynes, 30, was arraigned on the charge Wednesday. He was represented by his lawyer and did not appear in Halifax provincial court.

The alleged sexual assault occurred in Halifax some time between May 22 and May 25, 2013, according to the Nova Scotia Public Prosecution Service. Tynes is scheduled to be back in court on May 3.

Tynes is already facing two unrelated counts of uttering threats to cause bodily harm and one count of engaging in threatening conduct. Those charges relate, in part, to allegations he said he wanted to stab his dean at Dalhousie University and kill up to 20 people.

He pleaded not guilty to those charges in November.

He was charged with the threats in August, suspended from Dalhousie, and has been living with his father in Truro since September.

He is also charged with unauthorized possession of a prohibited device in relation to an overcapacity cartridge magazine. Police found a variety of guns and more than 1,800 rounds of rifle ammunition when they searched his home.