Japan is arranging to help domestic firms secure critical minerals such as rare earths by financially supporting their mining and refining businesses, as China, rich in such resources, tightens its export controls, a government source said Wednesday. The aid, likely in the form of investments and subsidies, is part of Prime Minister Sanae Takaichi's pledge to boost what she describes as "crisis management investment." It is expected to go into an economic package to be compiled later this month, according to the source.