Police from Milton Keynes and Aylesbury's region have been addressing money laundering issues in the area over the past month.
Officers from the South East Regional Organised Crime Unit (SEROCU) are combating money laundering which funds dangerous illegal activities.
Police reports suggest £12 billion is laundered in the UK each year and helps fund organised crime, human trafficking, and terrorism.
A Thames Valley Police spokesman said: "Assets from these crimes or any others need an outlet to launder the proceeds, therefore it is important to remove or educate at the point where criminals integrate their criminal money to prevent crimes being profitable."
SEROCU officers joined representatives from HM Revenue and Customs (HMRC) during February to carry out days of action to help prevent money laundering.
Representatives from both the police and HMRC visited businesses which operate by transferring funds to check they are aware of money laundering warning signs.
These are the outlets criminals often exploit so their cash assets can be integrated into the system, Thames Valley Police report.
On 8 February officers and HMRC visited 49 businesses in Slough and Berkshire running through responsibility checks the companies should be completing.
Two days later people involved in the project held discussions at premises in Woking.
Five days on, officials visited 27 companies in Brighton speaking to staff and dropping off leaflets with further information.
A couple of days later 20 Southampton businesses were targeted during another day of action.
Detective Chief Inspector Rob Bryant, of SEROCU, said: “Around £12 billion in cash is laundered in the UK every year so it is vital that we take action to tackle this issue and look to prevent it.
"These funds could be used to finance illegal activity such as organised crime, human trafficking or even terrorism.
“We are working together to make the region a harder place for criminals to launder cash and our aim is to deter the use of criminal cash.
“One of the ways money leaves the UK is via Money Service Businesses – so it is important these outlets are aware of their responsibilities and carry out thorough checks on their customers.
“By working together with HMRC, which oversees Money Service Businesses, SEROCU and the police forces across the south east were able to visit many premises to ensure they are aware of any warning signs. If Money Service Businesses do not comply with anti-money laundering regulations, they could face serious consequences such as fines or even criminal convictions.
“Whilst we discovered there were some knowledge gaps, most of the Money Service Businesses were happy to engage with us to enable us to work collaboratively to tackle and prevent the issue.
“We also used this opportunity to inform businesses about spotting the warning signs for other offences, such as ‘romance’ fraud, in which a person may be under duress to transfer money abroad and human trafficking.”
HMRC’s Matt Touzel the taskforce lead for the cross-government MSBs said: “HMRC is a fully engaged and active participant in cross-government and law enforcement agency work to tackle economic crime and money laundering. Cross-government cooperation is key to dealing with the menace of money laundering.
“The Money Laundering Regulations place robust and uncompromising obligations on MSBs to have appropriate policies, controls and procedures in place to protect themselves from criminals seeking to exploit them.
"MSBs must be vigilant in identifying those who seek to exploit them and comply in full with their obligations. We remain committed to helping MSBs who want to comply with the regulations whilst rigorously rooting out and tackling those who don’t.
“We have a vigorous programme of compliance inspections where we check that MSBs are complying with their anti-money laundering obligations, and we take a robust approach to those who don’t comply.”
HMRC has made more information about money laundering available to the public, which can be accessed online here.