Thai police issued two new arrest warrants and released images on Monday of more suspects, a Thai woman and a foreign man of unknown nationality, in the widening investigation into Bangkok's deadly bombing two weeks ago.

During a televised statement, police broadcast a photograph of the woman's Thai identification card showing a young woman in a black headscarf and a sketch of the man whose nationality was unknown.

The development came after police arrested a man from an apartment in Bangkok's outskirts on Saturday and seized bomb-making equipment that included detonators, ball bearings and a metal pipe believed to be a bomb casing.