There are many ways for cybercrime to take place
Cybercrime

Combating computer crime : Investigation

It is difficult to find and combat cyber crime’s perpetrators due to their use of the internet in support of cross-border attacks. Not only does the internet allow people to be targeted from various locations, but the scale of the harm done can be magnified. Cyber criminals can target more than one person at a time. The availability of virtual spaces to public and private sectors has allowed cybercrime to become an everyday occurrence. In 2018, The Internet Crime Complaint Center received 351,937 complaints of cybercrime, which lead to $2.7 billion lost.

They use their intelligence to protect against international cybercrime.
They use their intelligence to protect against international cybercrime.

A computer can be a source of evidence (see digital forensics). Even where a computer is not directly used for criminal purposes, it may contain records of value to criminal investigators in the form of a logfile. In most countries Internet Service Providers are required, by law, to keep their logfiles for a predetermined amount of time. For example; a European wide Data Retention Directive (applicable to all EU member states) states that all e-mail traffic should be retained for a minimum of 12 months.

There are many ways for cybercrime to take place, and investigations tend to start with an IP Address trace, however, that is not necessarily a factual basis upon which detectives can solve a case. Different types of high-tech crime may also include elements of low-tech crime, and vice versa, making cybercrime investigators an indispensable part of modern law enforcement. Methods of cybercrime detective work are dynamic and constantly improving, whether in closed police units or in international cooperation framework.

Senator Tommy Tuberville touring the National Computer Forensic Institute in Hoover, Alabama in 2021.
In the United States, the Federal Bureau of Investigation (FBI) and the Department of Homeland Security (DHS) are government agencies that combat cybercrime. The FBI has trained agents and analysts in cybercrime placed in their field offices and headquarters. Under the DHS, the Secret Service has a Cyber Intelligence Section that works to target financial cyber crimes. They use their intelligence to protect against international cybercrime. Their efforts work to protect institutions, such as banks, from intrusions and information breaches. Based in Alabama, the Secret Service and the Alabama Office of Prosecution Services work together to train professionals in law enforcement through the creation of The National Computer Forensic Institute. This institute works to provide « state and local members of the law enforcement community with training in cyber incident response, investigation, and forensic examination in cyber incident response, investigation, and forensic examination. »

Due to the common use of encryption and other techniques to hide their identity and location by cybercriminals, it can be difficult to trace a perpetrator after the crime is committed, so prevention measures are crucial.

Source : https://en.wikipedia.org/wiki/Cybercrime.