Violent burglars made off with jewellery worth more than £100,000 after a home invasion.
The incident happened in Caddington Close, East Barnet at 9.10am on Thursday, January 26.
Images of a man involved have now been released by police for help in their investigation.
The man knocked on the door of the house pretending to be a delivery driver, but pushed the resident back into the house when she opened the door.
The victim was a woman in her 60s, who was alone at the time of the attack.
She was hit with a black handgun and was forced upstairs with her hands tied behind her back with tape and cable ties.
The thug left the scene in a black Vaxhaull Insignia driven by another man.
The suspect is described as an Eastern European man with dark hair around 40years-old.
The eight item jewellery stolen included a diamond encrusted Cartier white gold love bangle valued at £35,000, Cartier earrings worth £15,000 and a £75,000 Tiffany ring with square emerald-cut diamond.
The CCTV images of the back of the man have been released five months later after police have exhausted all other lines of enquiry.
The police have also released images of the three items of jewellery listed.
Anyone with information about the items or suspect is asked to call Flying Squad officers in Putney on 101 or call Crimestoppers anonymously on 101.