A gang of violent armed robbers have been found guilty of raiding 10 banks and post offices during a £120,000 ($151,000, €141,000) crime spree lasting a year.

The six men terrorised staff and customers across south London during the raids between June 2014 and May 2015.

In total, the gang targeted eight high street banks owned by Barclays, HSBC, Natwest and Lloyds TSB, as well as two Post Offices.

Detectives said they would strike at opening time when they knew staff would be vulnerable.

So prolific were the robbers that police said the 2014 Christmas period saw them target three banks in just one day.

The men were convicted for a string of offences at the Old Bailey on Wednesday (25 January). They will be sentenced at the same court on 10 February.

Five of the gang had already been convicted of a £15,000 robbery of a Post Office in Croydon High Street, south London, in May 2015, during which two female staff members were pistol-whipped.

DC Adam Barsby, of the Met Police's Flying Squad, said: "The gang targeted post offices and banks at opening time when they knew staff would be vulnerable to attack. They used violence and a firearm to terrorise staff and customers, who didn't put up any resistance.

"They showed no emotion, compassion or forethought for the victims in these crimes and acted purely out of greed."

Gary Katabarwa, 29, of HMP Belmarsh, was convicted of nine counts of conspiracy to rob, one count of possession of a firearm with intent to cause fear of violence, and one count of money laundering.

Shane Perry, 34, of HMP Belmarsh, was convicted of five counts of conspiracy to rob, one count of possession of a firearm with intent to cause fear of violence and one count of money laundering.

Reece Perry, 24, of HMP Belmarsh, was convicted of three counts of conspiracy to rob and one count of money laundering.

Dwayne Ramsey, 35, of HMP Thameside, was convicted of six counts of conspiracy to rob and one count of money laundering.

Herbert Kulsumu, 36, of HMP Belmarsh, was convicted of one count of conspiracy to rob and one count of money laundering.

Olukayoade Conteh, 25, of HMP Brixton, had already been convicted and sentenced for his part in a robbery on 26 February 2015 at Lloyds Bank in Westow Hill. He pleaded guilty to one count of conspiracy to rob and one count of money laundering at the beginning of this trial and awaits a date for sentencing.

Reece and Shane Perry, Kulsumu, Katabarwa and Ramsey had already been convicted in December 2015 of the armed robbery at Croydon High Street Post Office on 26 May 2015.

The venues the gang conspired to rob were:

1. Post Office, Lower Addiscombe Road, Croydon on 26 June 2014

2. Lloyds Bank, Croxted Road on 11 July 2014

3. Barclays Bank, Westow Hill on 23 December 2014

4. HSBC Bank, London Road, Mitcham on 23 December 2014

5. Barclays Bank, Coombe Lane, Raynes Park on 23 December 2014

6. HSBC Bank, London Road, Mitcham on 12 February 2015

7. Lloyds Bank, Westow Hill on 26 February 2015

8. HSBC Bank, Ewell Road, Surbiton on 25 March 2015

9. Post Office, Lower Addiscombe Road, Croydon on 8 April 2015

10. Nat West Bank, High Road, Streatham on 1 May 2015.