Arrests are being conducted and searches are underway this morning around the North Kirklees area.
The arrests and searches are part of a National Crime Agency (NCA) money-laundering operation.
NCA officers, with support from West Yorkshire Police, are set to search addresses in Cleckheaton, Bradford and Dewsbury.
An NCA spokespersons said: “Today’s action is pre-planned and being carried out with the support of local police officers.
"The action is against people suspected of being involved in a money-laundering group.
"Residents should not be unduly concerned about public safety during today’s activity.”
The NCA leads the UK’s response to serious and organised crime.
More to follow.