The boss of a care home dubbed an anonymous whistle-blower at his company a "thick b***h".
Chris Mitchell admits sending the "curt response" to the anonymous person who wrote to him under a pseudonym.
The chairman of Park Lane Healthcare, which runs Magnolia House in Cottingham and The Manor House in Little Weighton, Yorkshire, claimed his "loyal staff" were well looked after.
He was responding to allegations that staff are made to work shifts that do not leave them with the legal amount of rest between working hours.
An anonymous source had emailed him with her complaints, claiming that they had as little as nine hours between shifts and weekly rotas scheduling some staff on seven days in a row.

In response Mr Mitchell called the whistle-blower a "thick b***h" and later said the complaint was "false".
He said it was "debilitating to be targeted in this way" after a tough 18 months for the care sector.
The whistle-blower had previously said: "This has been going on for years, the hours that staff have been expected to work are against the law.
"There are very few that have been there very long, the latest recruit left after about three days after realising what it was like and you can't blame them.
"If staff aren't happy with the way that they're treated they're just told that they can go and find a job somewhere else if they like, the place is always hiring because of that.
"The whole thing is disgusting, it does make you wonder if this was what we were clapping for during the pandemic?
"It isn't just one person, I've spoken to a neighbour who used to work for them who said it had always been that way, I don't understand how they think it is acceptable to push staff to breaking point like that?"
When contacted about the complaints, Mr Mitchell said the homes had received Good CQC reports for many years.
"We could not achieve that without looking after our loyal staff and ensuring good rapport and working conditions for them," he added.
"Many of them have been with us a decade or more.

"After a very tiring 18 months which all care homes have faced, it is further debilitating to be targeted in this way through social media, where people can hurl untruths and insults without being challenged fairly on the facts.
"We do not underpay our great staff teams in any way and one never knows whether to respond to this sort of thing or ignore. We are damned if we do and damned if we don’t.
"My HQ team and our manager there (herself with 16 years service with us!) have been through this anonymous email line by line and driven wild horses through the accusations made and we refute everything said, quite frankly.
"We greatly support and uphold the rights to anonymity as this helps whistle-blowers stand up when they witness bad care practice at care homes and elsewhere, but this gripe is pay and conditions.
"We have an open door policy regarding any kind of grievance and I as chairman and my Head Office team are highly visible in the home. Indeed my son is based there all week.
"We usually get this sort of thing from employees who have been dismissed or left under a cloud and then purport to be someone who works there in the present, thus contacting either the press or CQC.
"My curt response, which let us not disregard, was to an anonymous person, was ill judged, but born out of weariness at what is hopefully the end of an extremely trying time for everyone in the care sector."
Mr Mitchell said that his team work "tirelessly" but rarely get positive headlines for their work.
"It is unfair and easy to throw stones from behind a wall," he said.
"I love this fine sector and the reason I have the degree against my name was that in my mid-50s I studied for three years in all my spare time to gain it, nights and weekends, making me very unpopular with my wife of 42 years.
"I didn’t do it for a pay rise or a better CV, I did it to understand what our staff face every day, what residents living with dementia face every day and to fully appreciate how difficult it is for relatives watching the decline of their loved ones.
"This is not the actions of a guy that does not appreciate his staff teams. I do take offence though to false accusations, pouring cold water on all we try to achieve at Magnolia and elsewhere."