What actions must ground control take during a runway incursion?

In the case of a runway incursion, the primary responsibility of ground control is to ensure the safety of all aircraft on the ground and in the vicinity. This involves taking immediate actions to direct involved parties to vacate the runway. The safety of aircraft is paramount, and proactive measures must be taken to prevent potential collisions or accidents.

By directing the involved parties to vacate the runway, ground control can quickly mitigate the risk of an incident. This may involve issuing instructions to taxi clear of the runway or, if necessary, halting further movements until the runway is clear and safe for use. Ground control's prompt communication is vital in maintaining safety standards at the airport.

Other options such as instructing parties to continue taxiing could exacerbate the situation, while simply notifying the control tower and waiting for further instructions could delay necessary safety actions. Also, allowing aircraft to land without interruption would ignore the immediate safety concerns posed by the incursion. Thus, directing involved parties to vacate the runway is the most effective and safest response to a runway incursion.