They don't pursue. They stop, linger at the edge of the system as you go rocketing into the void, don't even move when you finally turn, stop, hang there in space facing them again. The same message barks out from the lead vessel over and over again, finally resolves itself to English as your ship's integrated intelligence begins to make sense of the chatter. The translation is rough, but you get the basics– the system is quarantined, the whole system, and anyone trying to break that quarantine will be destroyed by the flotilla of warships that belong to the alien race that has chosen to enforce it.
The name of the species doesn't come through– this might be a first contact situation. They don't volunteer any data about themselves or why the system is quarantined, and though you briefly consider asking them, you decide that discretion is the better part of valor in this situation and spin up your phasedrive instead. The integrated intelligence chooses a point of interest in the opposite direction from the ships while you make a notation in the database, upload it to the network. When the jump comes, you're grateful for it, breathe a sigh of relief as you leave Chi Jaramillo Cepheus 5n far behind.
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