Detectives are hunting a gang of thieves who targeted Asian families living in the Sutton Heath, Eccleston and Thatto Heath areas of St Helens.
Police say large quantities of high-value, distinctive Asian jewellery was stolen during the raids.
Officers are probing six incidents between Janaury 8 and 27.
Similar burglaries also took place in Woolton and Upton.
Chief Supt Louise Harrison said: “Burglary is a very personal crime and understandably the victims have been left distressed by these incidents, with high-value and often very sentimental pieces of jewellery being stolen.
“We are carrying out extensive enquiries and taking a coordinated approach to investigate them - we are examining CCTV, and making house to house enquiries as well as carrying out forensic examinations of all of the scenes, to trace those responsible.
“We are also working closely with members of the Asian community – officers from the force’s Community Engagement team have been liaising with community leaders and this week have visited a number of community centres across Merseyside to speak with members of the community and to provide crime prevention and security advice.
“A leaflet around crime prevention advice has also been made available to the community and each of the force’s Area Commanders has been notified about these incidents, so patrols and high-visibility policing has been increased where necessary."
She added: “Everyone has the right to feel safe and secure in their own homes and I would ask anyone with any knowledge of these incidents to think about how they would feel if this was their home and their items?
“It is rare that people from this community have been targeted in this way and it is important that these offenders are brought to justice.
“Any information about these incidents could be vital to our investigation and I would urge anyone with any information to get in contact.”
Officers would urge anybody with any information about these incident to contact 101 or Crimestoppers anonymously on 0800 555 111.