Marian Bates was killed by robbers last week

The men were detained earlier this week in connection with the theft of the scooter used by the robbers.

Mrs Bates was shot during a raid at her shop in Arnold on 30 September.

The two assailants fled the scene on a stolen blue Gilera Runner scooter despite the attempts of members of the public to stop them.

Armed police

A police spokeswoman said: "It would be wrong to make the assumption that these people are connected to the murder.

"Those arrested are all male and aged between juvenile and mid 20s."

Detective Chief Superintendent George Frame, who is leading the murder inquiry, said this week his officers were making good progress in the hunt for the killer and his accomplice.

He said: "Officers are working extremely long hours and making very good progress, but we still urge the public to come forward with information.

The arrests appear to be linked to a large scale operation in the Basford area of Nottingham.

The raids are reported to have involved armed police and officers equipped with riot shields.

The men are being held at several Nottingham police stations.