Adding time onto the CSGO round timer when a specific event happens

Basically I’ve created a simple little vehicle-based map, where the objective is for the T’s to steal a car from the CT’s and bring it back to their spawn.
It’s working pretty well, but there’s one crucial thing I want to implement; an addition of two minutes should be added onto the round timer as soon as the car’s been entered. The time should obviously only be added once.

How do I do this? I’ve googled around, but I’m unable to find anything helpful