Radio clubs independent of the ARRL and ARES also participate in emergency communications activities in some areas, and some non-radio organizations have their own amateur arm. The Department of Defense sponsors the Military Auxiliary Radio System (MARS) program which utilizes Amateur Radio operators for emergency communication using military radio frequencies. The National Weather Service Skywarn weather-spotter program has a strong amateur radio contingent. And amateurs dedicated to the Salvation Army are organized under their Salvation Army Team Emergency Radio Network program.