This paragraph applies if a relevant officer has reasonable grounds to suspect that an offence under section 25, 25A or 25B has been, or is being, committed on the ship.

The relevant officer may arrest without warrant anyone whom the constable or officer has reasonable grounds for suspecting to be guilty of the offence.

The relevant officer may seize and retain anything found on the ship which appears to the officer to be evidence of the offence (but not including anything that the constable or officer has reasonable grounds to believe to be an item subject to legal privilege).

A power conferred by this paragraph may be exercised on the ship or elsewhere.