Faint submillimeter sources detected with JCMT/SCUBA
have faced an identification problem due to their broad beam profiles.
Here we propose a new method to identify these sources
at the mid-infrared utilizing a finer point spread function.
ISOCAM has provided us a very deep 6.7 μm image of the Hawaii Deep Field SSA13.
For all three 850 μm sources in this field,
we have found their 6.7 μm counterparts.
All of them have been identified with interacting galaxy pairs at the optical.
Two of the pairs are very faint and red (I>24, I - K > 4),
one of the two has the hard X-ray detection with Chandra.
Assuming an Arp 220 SED,
we have found a typical redshift of z ~ 2.
This requires
that the sources should be a few times more luminous than Arp 220.
It appears that extremely high star formation rates
are occurring in galaxies at high redshift
with massive stellar contents already in place.