The publisher of a flight simulator site targeted by a hacker in May says it has presented a file of evidence to UK police identifying the perpetrator.
Avsim said it had "incontrovertible evidence" about the hacker’s identity.
The attack wiped data held on two servers and "effectively destroyed" the site, which is still being rebuilt.
The US firm said it expected the criminal complaint, filed with London police, to lead to the alleged hacker spending "time behind bars".
"We will not name any names, but have incontrovertible evidence of the individual that performed the hack," said Tom Allensworth, the publisher and CEO of Avsim.
"We have protected the forensic evidence and provided that evidence to the London police. We are committed to bringing justice to bear on this case."
Mr Allensworth told BBC News that the evidence was submitted to the Southwark division of the Metropolitan Police, which was "acting on behalf of another constabulary".
The US site, launched in 1996, covers all aspects of flight simulation, although its main focus is on Microsoft’s Flight Simulator.
In addition it hosts a forum and allows enthusiasts to download extra content for flight simulations, such as new landscapes.
The firm claims it is the most-visited flight simulation site on the internet.
"Its contribution has been immeasurable," said Derek Davis, editor of PC Pilot magazine, following the attack.
The firm said it had spent $50,000 (£30,000) to bring Avsim back online since the 12 May attack, including $25,000 from users.
It said it had filed the criminal complaint after giving the alleged hacker "two opportunities to settle" the case.
"The individual did not avail himself of the opportunity – in fact, he has ignored our proffers," Mr Allensworth said in the statement.
"We are now doing as we promised this person we would do: ratcheting this up to the next, criminal, level."
"We fully expect that the criminal complaint filed today will result in the perpetrator spending some time behind bars – under UK law."
The firm said it was seeking prosecution under laws that "deal with unauthorised use of a computer, unauthorised and criminal theft of data, and numerous other violations of other computer and online laws".
The Metropolitan Police could not confirm whether it had received the complaint.
Source: BBC News