How would I detect flag captures?

Leaderboard Script

local stats = {"value", "Omegite"}

game.Players.PlayerAdded:connect(function(player)
    local leaderstats = Instance.new("Model", player)
    leaderstats.Name = "leaderstats"
    for _, stat in pairs(stats) do
        Instance.new("IntValue", leaderstats).Name = stat
    end
end)

Take this as a question and not a request. I would like to detect when a red or blue team member captures the flag and adds a point to a intvalue which is in workspace. What events would I use to detect when someone has captured a flag? FYI: The game I have makes you spawn in a lobby and picks a map after 25 seconds of waiting in the lobby.