A man in the 1980s was arrested on suspicion of killing an older woman.
The police hurried to a house in Kingsbury Avenue, Dunstable, just after 1.40 pm on Thursday and found a woman, also in her 80s, who was seriously injured.
The victim was declared dead on the spot a short time later.
Detective inspector Verity McCann said: “This is a tragic incident and our thoughts are currently among the loved ones of the woman.
'They are informed and are supported by our family businesses.
“One person is currently in custody in connection with this incident and there is now an investigation underway.”
The police were called to a house in Kingsbury Avenue on Thursday afternoon, Dunstable to report that a woman was injured in her 80s
A study was started by the Major Crime Unit of Bedfordshire, Cambridgeshire and Hertfordshire.
Anyone with information is asked to contact the police via the police website of Bedfordshire or up to and including 101 using Operation Eisele.