They were taken from a factory on the Sittingbourne Industrial Park last Monday, 7 May, after thieves made a hole in its metal and asbestos wall.

The ingots - which are highly dangerous if heated - were stacked next to a wall in a cellophane shrink-wrapped bale.

They measure about 2ft by 4in by 2in and look like aluminium, which is why police think they were taken.

Large vehicle

Officers said half of them had a brown and white painted edge, while the others had a green painted edge.

They all had the word MEL in raised lettering on the top face.

It is believed a large vehicle would have been needed to carry them all.

Anyone with information, or who was in the area between 1330 and 1820 BST, is asked to contact Kent Police.