The victim, a woman in her 20s, was approached by a man on a bike and another who was walking on Old Langho Road, towards Salesbury Hall Road, at around 5.10pm yesterday (November 19).
The pair then grabbed the woman by her throat before punching her in the face, causing "severe bruising."
The victim screamed she had a baby which prompted the offenders to make off towards the A59, leaving the mum and baby boy badly shaken.
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Officers have confirmed the baby boy was not injured in the attack, but the victim later noticed her Bose headphones were missing.
Det Sgt Sarah Hargreaves, of Lancashire Police, said: "It was a cowardly and despicable act which has left the victim very shaken and upset. Thankfully her baby was unharmed.
"We are appealing to anyone with information, or who witnessed the attack, to come forward. If you have any dashboard mounted camera footage which may show the robbery, or recognise the men described, please get in touch.
"We understand a motorist driving a silver Range Rover, with a partial registration plate of PK14, passed the scene shortly after the incident – did you see what happened?"
The man riding the bike has been described as white, 6ft 4in tall, aged in his mid-20s, with a thick, well-groomed beard.
He was wearing black, baggy clothing, with white trainers and had a black, beanie-style hat. He also had black gloves, partly reflective, with his mountain bike described as having thick, chunky tyres.
The second offender was described as wearing a coat.
Police say they recognise this is a very concerning incident for the local community and they are urging anyone walking in the area to be vigilant.
They have also confirmed patrols have been increased in the area and a specialist team of detectives are working on the investigation.
Anyone with information can contact police by calling 101 or emailing [email protected], quoting log number 1129 of November 19.
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