According to the agency that took the photos, the man tried to confront Pam on the train, but was removed from the train by British Transport Police. According to the cops, the man eventually became violent and assaulted one of the officers.
The man was then pepper sprayed and taken away by several police officers (see above). According to several UK outlets, the same man has been bothering Anderson for weeks, causing her to use extra security.
A rep for Anderson described the events as follows, via Twitter: "Pamela Anderson is safe and sound on train back to the English capital -- no problems with her safety due to excellent security personnel."
Anderson is in London appearing as a sexy genie in a stage version of "Aladdin."