Two women were robbed of their handbags in the space of an hour.
Both robberies happened in the Eccles area of Salford and on both occasions, the victims were grabbed in headlocks before their handbags were stolen.
Police are treating the incidents are linked and believe the same offenders were responsible for both robberies.
The first happened at about 10.45pm on Saturday 4 September 2012. The 62-year-old woman was out walking alone on Trafford Road in Eccles when she was confronted by two men who grabbed her by the head to restrain her, before running off with her bag.
A passer-by stopped to comfort her and the police were called.
The main offender was described as being black or Asian, about 5ft 6in tall, with short dark hair and of a slim build. He was wearing tight red chino-style pants, a dark-padded sleeveless jacket and a light-coloured hooded top underneath.
The second man was said to be taller and of a bigger build than the first offender, and wearing dark knee-length shorts in a check design and a dark sleeveless hooded top with a light top underneath.
About an hour later, on Wellington Road in Eccles, another woman who was walking from Eccles town centre towards Lyntown Trading Estate was approached by two Asian men and was also grabbed in a headlock and her bag stolen.
The woman tried to give chase to the two thieves but lost sight of them.
Police are now appealing to anyone who has information about either robbery to come forward.
The description for the offenders in both incidents is very similar - with one man said to be wearing the red trousers and the other the check shorts.
Police Constable Fiona Butler said: "Based on the similar descriptions of the offenders and the modus operandi for each crime, we believe the same men are responsible for each robbery.
"These are two despicable, opportunistic crimes committed against defenceless women out walking alone.
"One of the women is now too frightened to go out and will not walk anywhere, such is the profound effect this has had on her. That is totally unacceptable - no-one should be made to feel that way.
"Therefore we need to find these two men and give these women the justice they deserve.
"We believe they are local to the area as they had good knowledge of the back streets of Eccles which helped them to evade capture. However we will do everything we can to find them and I would appeal to anyone in the community, and even the friends and family of the offenders themselves, to do the right thing and come forward."
Anyone with information should call police on 0161 856 5250 or the independent charity Crimestoppers, anonymously, on 0800 555 111.