Video footage shows a rescue helicopter landing at Wells Cathedral in Somerset, to rescue a woman trapped between two turrets.
The 60-year-old is believed to have fallen 30ft after plunging through a void in a wall, while on a tour of the cathedral.
An Avon and Somerset Police spokeswoman said a helicopter from RAF Kinloss in the north of Scotland airlifted the woman to Frenchay Hospital in Bristol, with what are believed to be arm and pelvic injuries.
Two people have been arrested in connection with slavery offences in South Gloucestershire and Bristol, police said.
The three alleged male victims, one in his 30s, one in his 40s and one in his 50s have been taken to a place of safety.
The police said in a statement they have also arrested five others on suspicion of offences including failing to appear, cannabis production, money laundering and handling stolen goods. A significant quantity of cash was found at one of the addresses.
Avon and Somerset police officer Christopher Hardaway remains in hospital after falling through a garage roof while pursuing a suspect in Bristol.
The officer, who is in his 20s, suffered serious head injuries after plunging through the roof of a car mechanics' premises in Hampton Road, Redland, this morning.
He had been on patrol with a colleague when they noticed a man acting suspiciously.The police helicopter was called to help the search and reported that a man was on the roof of the Bristol 2CV garage.
Pc Hardaway climbed on to the roof to look for the man but fell through it. He was taken to Frenchay Hospital, where he remains in a critical condition.
Police officers have paid tribute to "one of the best" - a police dog who racked up more than 200 arrests in one year.
Former Avon and Somerset police dog Roo died in his owner's arms on Wednesday.
Roo received a commendation for his outstanding arrest rate after detaining 202 suspects at the age of five.
He retired four years ago after a six-year career with Avon and Somerset Police, where he was responsible for more than 70 percent of canine catches.
Roo's handler, Pc Jim Hampson, said: "Roo was an absolutely brilliant police dog - the perfect partner. He was totally driven and exceptionally brave - saving my life on more than one occasion. He became a bit of a legend in the force."
Inspector Andy Roebuck, who is in charge of the force's dog unit, said: "Police dogs are vital to operational policing and are extremely effective in a wide range of situations from searching, detecting people, drugs or explosives to crowd control and detaining criminals.
"Not every dog we start training makes it through to become an operational dog, it takes a lot and Roo was one of the best."
Roo retired in December 2009 and went to live with a friend of Pc Hampson, who visited him regularly.