Yes, the crew of the HMS Cossack did arm themselves with cutlasses, pistols, rifles and SMGs when they boarded the German tanker Altmark in Norwegian waters on the 16th of February 1940.

The Altmark carried 299 British sailors captured by the pocket battleship Admiral Graf Spee during her raids in the southern Atlantic, all of which were freed by the crew of the HMS Cossack.

The British did not know where the British sailors were held, and rifle and pistol fire might penetrate walls and doors of the German tanker and potentially wound or kill their own captive men. In the close and cramped conditions inside a ship, combat distances would be very short, and a bayonet and a cutlass might actually be a better weapon than a rifle under such conditions.

That said, the Altmark was a civilian tanker and did not have much of and armed crew aboard (there certainly were some light arms).