Two peculiar icy objects were recently found by the infrared satellite AKARI (Onaka et al. 2021). Both objects show deep ice absorption features that are often seen in embedded young stellar objects (YSOs) or background stars sitting behind dense clouds, however, they are located neither in known star-forming regions nor in known dense clouds. Their infrared SEDs show a peak around 5 micron, which are incompatible with existing SED models of embedded YSOs. If they are truly YSOs, similar objects should have eluded past photometric surveys, which would require a revision of our view of the distribution of YSOs in our Galaxy. If they are background stars, there must be dense and very compact starless clouds in the line-of-sight, which have eluded past dense cloud surveys, or ice species may grow in unknown processes in tenuous clouds. Either case will make a significant impact on our understanding of the ice chemistry and/or star-formation process in our Galaxy. To reveal their nature, we recently carried out submillimeter observations with ALMA (12m+ACA). Very compact emission of CO(3-2) and SiO(8-7) are detected at the positions of two icy objects. The observed large integrated intensity ratios of SiO(8-7)/CO(3-2) (~0.3-0.4), as well as their broad line widths (8-15 km/s), imply the contribution from shocked gas. Although a large dust extinction (Av ~80-120 mag) is implied from their deep dust/ice absorption bands, no dust continuum emission is detected. We will discuss a possible nature of those peculiar icy objects in this poster.