Detectives in Chorley today said women at home alone should not answer the door.
Police today revealed a pattern in crimes where family homes are broken into when Asian women are on their own.
One was even tied up in her house while the thugs stole jewellery in an incident, in Worthy Street, on January 13.
The three men used tape to bind the victim’s hands, feet and mouth.
They threatened her with a knife and made demands for money and jewellery.
The latest incident took place in Stump Lane on February 14 when a mum was home alone with her children.
The youngsters managed to raise the alarm before the men were able to gain access to the property.
Police are now warning the public about the spate of attacks, after four more happened in Preston and Blackburn.
Neighbourhood police officers in Chorley are working closely with Coun Hasina Khan, who represents Chorley East on Chorley Council, to reassure Asian women in the area.
They are also issuing safety advice at Asian Women’s Forums held on Saturdays at the Lord Street Community Centre.
Detective Constable John Pearce from Chorley CID said: “The victims in these offences have faced a terrifying ordeal.
“These incidents have understandably prompted a great deal of anxiety and fear, particularly among the female Asian community.
“Our officers are working hard to reassure residents and provide important safety advice. I would urge anyone with information which could help detectives with this enquiry to contact us as a matter of urgency.
“The message we are sending out to the community is that lone women should never open the door to people they do not know and should always check through a peep-hole first and keep any security chain or bolt in place.
“It is important that people need to establish the identity of visitors before opening the door.
“If in any doubt contact the police.”
Anyone with information is asked to call Chorley CID on 101.