Four containers contaminated by nuclear radiation will be delivered back to Japan by the end of the next week, said sources in Ain Sokhna port, after Japan authorized the return. The port authority sent a fax requesting Japan receive the four contaminated containers, the sources reported. Two of the impounded containers belonging to contracting companies Al Nour and Riyad will be sent first, and the other two containers will be sent later. The impounded containers are quarantined to avoid human infection, sources said.