can you get prosecuted for a crime in country(A) for a crime that took place in country (B)?
<p>if (Bob) who lives in country(A) infringes copyright of citizens of country (B) and hacks into country(B) government servers and continues to do crime against  country(B),if country (A) and country(B) have no extradition treaty with eachother:</p>

<ul>
<li><p>is there any way that country (B) would be able to arrest or stop (Bob) from continuing his attacks?</p></li>
<li><p>can country(B) prosecute (Bob) in country (A) because black hat hacking is also illegal in country(A)?</p></li>
</ul>

<p>First, it depends on whether <a href="https://en.wikipedia.org/wiki/Trial_in_absentia" rel="nofollow noreferrer">trial in absentia</a> is legal in the prosecuting jurisdiction. In the US, trial in complete absentia is prohibited by the due process clauses of the 5th, 6th, and 14th Amendments. Italy on the other hand does allow such trials. Second, even if a person is convicted in absentia, that does not mean that the perpetrator is stopped in any sense. This being about law, I will not discuss the option of illegal enforcement (even when legal under the laws of the prosecuting country), however this is an obvious way to overcome the lack of an extradition treaty. In general, if a nation will not extradite a person to another for prosecution, they also will not enforce a foreign judgment against the person. An extradition treaty may not be necessary: if it is legal for country B to expel undesirable aliens (or citizens), that could open an avenue for legal arrest (in country C).</p>

<h2>Yes, they can arrest or stop Bob</h2>

<p>If Bob is committing an act of war against country B then, under the laws of B and international law (but not necessarily the laws of A), B can kill Bob. Drone strikes, assassination or special operations teams are the usual methods, actual invasion of of A by B are relatively rare but the first and second Iraq Wars are examples.</p>

extradition