Security is being reviewed at a hospital after a nurse was stabbed in the car park at the end of her shift.
The woman was getting out of her car in the hospital car park
The woman, who is in her 50s, is in a stable condition after being attacked outside Birch Hill Hospital, Rochdale.
Her employer, Pennine Care NHS Trust, said that security at the site had been improved over recent weeks.
Unions said they had been calling for better protection for three years. A 15-year-old boy has been arrested on suspicion of wounding.
The woman, who is from Rochdale, was stabbed on Sunday night as she got out of her car.
'Shocked and distressed'
She had finished work, but is believed to have forgotten something and was going back.
Unison said it had campaigned for increased security on all of the sites operated by the mental health trust, which includes Oldham, Tameside, Stockport and Bury.
"In particular we have been calling for a security presence and CCTV improvements at the clock tower building at Birch Hill," it added.
Officials at Pennine Care said they were "shocked and distressed" at the stabbing.
"Executive directors and senior managers are currently on site reviewing the incident and security," a spokeswoman said.
"Staff safety is a priority for the trust and procedures are in place to promote staff safety.
"There are public rights of access across the Birch Hill site, but we can confirm that the trust has improved security arrangements over recent weeks.
"In particular there are procedures in place for managing staff safety on the site which involve security escorts at the beginning and end of shifts."