3.—(1) If the commander of an aircraft registered in a Tokyo contracting state has reasonable grounds for believing that a person has committed, or is about to commit, on board the aircraft in flight anywhere any act which—

(a) if committed in the state in which the aircraft is registered would constitute an offence under the law in force in that state, or

(b) jeopardises or may jeopardise—

(i) the safety of the aircraft,

(ii) the safety of persons or property on board the aircraft, or

(iii) good order or discipline on board the aircraft,

the commander may take, with respect to the person, such reasonable measures, including restraint of his person, as he reasonably considers to be necessary—

(i) to protect the safety of the aircraft, or of persons or property on board the aircraft,

(ii) to maintain good order and discipline on board the aircraft, or

(iii) to enable the commander to disembark the person or to deliver him to a member of the Garda Síochána in the State or to competent authorities outside the State, as the case may be, in accordance with the provisions of this Act.

(2) For the purposes of subsection (1) of this section, the commander of an aircraft may—

(a) order or authorise the assistance of any other member of the crew of the aircraft, or

(b) request or authorise the assistance of any other person on board the aircraft.

(3) Any member of the crew of an aircraft which is in flight, or any other person on board, may, without being ordered, authorised or requested by the commander of the aircraft take, with respect to any other person on board the aircraft, any reasonable measures which he has reasonable grounds for believing to be immediately necessary to protect the safety of the aircraft or of persons or property therein.

(4) Any restraint imposed on a person on board an aircraft under this section shall not be continued after the time when the aircraft first ceases to be in flight and the person is handed over to a member of the Garda Síochána in the State or to competent authorities outside the State, as the case may be, unless—

(a) the place where the aircraft first ceases to be in flight is in the territory of a state which is not a Tokyo contracting state and which refuses to permit that person to be disembarked,

(b) the measures of restraint were imposed in order to enable the person to be delivered to competent authorities in the state of registration of the aircraft (being, in the case of the State, a member of the Garda Síochána),

(c) the aircraft has made a forced landing and the commander is unable to deliver the person to competent authorities (being, in the case of a forced landing in the State, a member of the Garda Síochána), or

(d) the person under restraint agrees to continue his journey under restraint on board that aircraft.