Armed robbers threatened Post Office staff with a knife before fleeing with cash.

One man has been detained in connection with the incident at Granton Post Office on Friday morning but two others are at large.

The incident took place at the post office within the Sandy's newsagent on Granton Mains Avenue near the junction of West Granton Road, at around 9am.

The suspects threatened staff members with the knife and stole a "sum of money", police said.

They fled in a black Mini Cooper with the registration number SM15 UXB and were last seen heading south on Granton Mains Avenue.

One of the suspects is described as white, in his early 20s and wore a grey tracksuit, black puffa jacket with a tracksuit top underneath, black trainers with white soles and black gloves.

There is no description of the second suspect.

Detective sergeant Robbie Wallace said: "Crimes of this nature are rare for Edinburgh and an extensive investigation is now underway to trace those responsible.

"No one was injured in this incident however staff members within the shop were left badly shaken.

"At this time we're pursuing all lines of inquiry and I urge anyone with relevant information to come forward."

Anyone with information is asked to contact police on 101 or make an anonymous report to Crimestoppers on 0800 555 111.