Some people in the wrong place at the wrong time is a scripted special encounter in Fallout 2. It will take place on August 30th, 2241 when traveling the world map, or if in a world map location on this date, the encounter follows as soon as the Chosen One enters the world map again.
The Chosen One stumbles upon a confrontation. On the right side, two Enclave soldiers wearing advanced power armor and armed with miniguns, and Frank Horrigan, one of the Enclave's Secret Service agents. And on the left side is a farmer, his wife, and their small child, all of which are unarmed and unarmored.
Frank Horrigan demands the man and his family to come with him and his men immediately, to which the farmer refuses, demanding to be left alone as he will never support the cause of their [the Enclave's] superiors. After, Horrigan issues a second and final warning to the farmer and his family, or that "they will be made an example of". 
Still refusing to comply with the new strange group, the farmer replies that he would rather what knowledge he has disappear with him into the grave. With that, Horrigan orders his two troopers to kill them all, and they are promptly executed, dying rather gruesomely at the unleashing of two discharging miniguns upon them.
Horrigan and his troopers then wave the Chosen One away, stating to them it is none of their [the Chosen One's] business, and that they should turn around and walk away.
- This is the first time the Enclave and Frank Horrigan are encountered in Fallout 2, and the scripted nature of the encounter virtually guarantees this to be found relatively early in the game.
- It is unknown what knowledge or otherwise that the man representing the family possessed or withheld that so interested the Enclave enough, that they sent one of their deadliest weapons of all, Frank Horrigan, to intervene directly. The reasoning for, and/or the backstory behind whatever happened beforehand that led to this event, is never clarified after it occurs.
- While the exact answer is unknown, in Fallout Bible 4 Chris Avellone provides his personal assumptions saying that the farmer may have known "key information on the possible location of a Brotherhood of Steel outpost/bunker, some key genetic research that would enable the researchers to finally decode the FEV and/or figure out how to release it" or that perhaps he was "an escaped Enclave scientist".