A man has been arrested after the death of a 49-year-old woman who was doused with petrol and set alight.
The 50-year-old was spotted by an off-duty police officer getting off a train at Marple railway station and armed officers were sent to arrest him, Greater Manchester Police said.
He is currently being questioned on suspicion of murder.
Authorities had previously issued an appeal for help in finding Stephen Archer, 50, in connection with the incident.
Police had been called to reports that a man had deliberately set a woman on fire at a house in Newton Heath, Manchester, just before 9.45am on Monday.
The victim, reported to be Mr Archer's sister, suffered burns to 70% of her body and was taken to hospital but police say she has now died, prompting a murder investigation.
A second woman, 19, escaped without injury from an upstairs window of the house.
Superintendent Arif Nawaz from GMP's North Manchester Division said specialist officers are supporting the woman's family as they "come to terms with the worst possible news".
He added: "At this stage I would also like to thank the public for their continued support throughout this difficult and protracted investigation.
"We always aim to bring an incident like this to a safe conclusion and I am pleased to say that, as a result of the quick actions of an off-duty officer plus the professionalism of our armed officers, we have now resolved what could have been an even more serious situation.
"However, the fact we have made an arrest does not mean the investigation ends here - far from it."
:: Anyone with information can call police on 0161 856 2491, 999, or Crimestoppers, on 0800 555 111.