Or the apartment bombings debacle, where the GRU and FSB launched false flag bombing attacks against it's own citizens. Several of them were arrested by police planting bombs. At one point a Duma representative denounced 'breaking news' of an attack by 'terrorists' in a specific location 3 days before it actually happened.
Not to mention generating exodi from Venezuela and Syria just so that your puppet candidates in the US and the EU can rally against the "invasion" of refugees.
Letting in a large amount of people to enter a country without the necessary visas, technically is an invasion. Otherwise what's the point of country borders and border enforcement? If strangers could come and go in your house as they please without your permission, that's illegal as well and you'd call the police.
Pretty sure this had nothing to do with trains or negotiating with terrorists. A closer comparison would be a recent event during which a military prevented kidnappings by killing the people who could be taken as hostages.
https://en.wikipedia.org/wiki/1999_Russian_apartment_bombing...