If the condition applicable to this subsection is satisfied, any constable of a police force in England and Wales who has reasonable grounds for suspecting that an offence has been committed or attempted in England or Wales and that the suspected person is in Scotland or in Northern Ireland may arrest without a warrant the suspected person wherever he is in Scotland or in Northern Ireland.
If the condition applicable to this subsection is satisfied, any constable of a police force in Scotland who has reasonable grounds for suspecting that an offence has been committed or attempted in Scotland and that the suspected person is in England or Wales or in Northern Ireland may, as respects the suspected person, wherever he is in England or Wales or in Northern Ireland, exercise the same powers of arrest ... as it would be competent for him to exercise were the person in Scotland.
The powers conferred by subsections (1) and (2) may be exercised in England and Wales and Scotland by a constable appointed under section 24 of the Railways and Transport Safety Act 2003 or under section 55 of the Energy Act 2004.
If the condition applicable to this subsection is satisfied, any constable of a police force in Northern Ireland who has reasonable grounds for suspecting that an offence has been committed or attempted in Northern Ireland and that the suspected person is in England or Wales or in Scotland may arrest without a warrant the suspected person wherever he is in England or Wales or in Scotland.
The condition applicable to subsection (1) above is that it appears to the constable that it would have been lawful for him to have exercised the powers had the suspected person been in England and Wales.
The condition applicable to subsection (2) above is that it appears to the constable that it would have been lawful for him to have exercised the powers had the suspected person been in Scotland.
The condition applicable to subsection (3) above is that it appears to the constable that it would have been lawful for him to have exercised the powers had the suspected person been in Northern Ireland.
It shall be the duty of a constable who has arrested ... a person under this section—
and to do so as soon as reasonably practicable.
The following provisions apply in relation to an arrest under this section by a constable under subsection (1) or (3)—
Where a constable arrests a person under a power exercised by virtue of subsection (2) above, any enactment or rule of law which concerns—
applies in relation to the arrest (subject to the modifications set out in section 137ZA) as though the arrest had been effected in Scotland and, if the constable who executed it is not a constable of a police force in Scotland, as though the constable were.
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In this section—
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“designated police station” has the same meaning as in the Police and Criminal Evidence Act 1984 or, in relation to Northern Ireland, as in the Police and Criminal Evidence (Northern Ireland) Order 1989; and
“constable of a police force”, in relation to Northern Ireland, means a member of the Royal Ulster Constabulary or the Royal Ulster Constabulary Reserve.
This section shall not prejudice any power of arrest conferred apart from this section.