A man 10 days out of prison has been charged with violently attacking a woman who was working the overnight shift alone at a gas station in Dartmouth, N.S.

The clerk remained in critical condition in hospital Tuesday after undergoing surgery.

A woman was attacked while working alone at this Ultramar gas station on Tuesday.
(Rob North/CBC)

Meanwhile, the man accused of sexually assaulting and trying to kill her, Michael Derrick Robicheau, 32, appeared in court and was ordered to undergo a psychiatric evaluation.

Steve Ecclestone, general manager for Ultramar gas stations in the region, said the clerk was working alone when her attacker buzzed to be let in through the locked door.

The woman, 44, called police from the gas station on Portland Street just after 2:30 a.m. Tuesday and said she had been sexually assaulted and cut with a knife.

Police said the clerk was unconscious when officers and paramedics arrived, and she was rushed to hospital with life-threatening injuries.

About 20 minutes after the attack, the police dog unit found Robicheau in bushes near a ramp leading to Highway 111.

Robicheau was released from prison 10 days ago after serving two-thirds of his sentence for numerous convictions. He has a long criminal history, including a conviction for attacking a clerk in a sandwich shop.

He has now been charged with attempted murder, sexual assault, assault and robbery. He is scheduled to return to court on Sept. 11.

The Ultramar gas station was shut down Tuesday as police and forensic investigators combed the area for evidence.

"We've never had something like this, of this magnitude or seriousness, happen," said Ecclestone, adding Ultramar will review how late shifts are managed.

He said the clerk apparently did not use a panic button.

Graham Conrad, with the province's gas retailers association, said businesses should double up their staff on overnight shifts.

With files from the Canadian Press