Arrests of three men and a woman have been made in the last week.
Detectives are investigating a spate of burglaries which have specifically targeted premises linked to Chinese restaurants and take-aways.
DCI Russell Jenkins, of South Wales Police, said the behaviour will simply not be tolerated.
“Incidents of this nature are extremely distressing for victims,” said DCI Jenkins.
“We are investigating several burglaries which have happened since mid-January. We are working with our partners and members of the communities affected to offer additional crime prevention advice to the business owners.
“These offences have impacted several forces areas including our own. The others are Gwent, Dyfed-Powys, Gloucestershire, and Avon and Somerset Police.
“We are working in partnership and collaboration with our colleagues from these force areas to investigate further these matters.”
Inspector Kee Wong said it is now the job of the police to build confidence back in the communities affected.
“Since these burglaries began a number of neighbourhood officers have being paying frequent visits to these businesses across the force area providing crime prevention messaging and reassurance to the Chinese community,” said Inspector Wong.
“We will continue to engage closely with the community as the investigation progresses.”
If you have any information relating to these incidents, contact the police, quoting reference: 2300043553.