A man has been arrested in connection with an attack and robbery on a 76-year-old man in his Derby home.
The elderly man was tied up, threatened at knifepoint and punched in the face by robbers at his house on Brackensdale Avenue in Mackworth on Tuesday night.
A 34-year-old man was arrested, questioned and bailed, pending further inquiries, police said.
The intruders, who wore balaclavas, stole cash and financial documents. Police appealed for information.
Det Insp Mark Argyle from Derbyshire Police said: "We don't believe that this was a random attack and we think the offenders are likely to have known the victim.
"We are still anxious to hear from anyone who was in the area of Brackensdale Avenue of Mackworth between 2200 GMT on Tuesday 28 December and 0100 GMT on Wednesday 29 December."