The grandson of prominent anti-gun campaigner Pat Regan has been arrested on suspicion of stabbing her to death.
Mrs Regan, 53, was discovered at the property on Marlborough Grange in the Hyde Park area of Leeds on Sunday.
The mother-of-six started campaigning against gun crime when her son Danny was shot dead in 2002.
The 20-year-old man was being held on suspicion of murder, police said. It is thought he had been arrested earlier in the day over another stabbing.
I've some sympathy for her, given the circumstances:
Mrs Regan set up a Leeds branch of Mothers Against Guns after her son Danny, 25, was shot at his home in Haydock, near St Helens, Merseyside in December 2002. His killer has not been found.
Unfortunately, Mrs. Regan's death proves in a rather stark way that controlling the tools used in crime is not a valid method of controlling crime. Criminals just find other tools.
Flip o' the tentacle to The Ready Line for passing on the story.