The solar submillimeter-wave telescope installed in El Leoncito (SST), Argentina Andes, was considerably improved. It operates with four 0.2 THz and two 0.4 THz radiometers in the focal plane. A new solar flare terahertz emission component was detected, spectrally separated from the microwave emissions. Burst pulsations are common to all events observed. There is a suggestive association between the pulsations onset and the launch time of CMEs. Rapid pulsations exhibit repetition rates proportional to fluxes, suggesting discrete and quantized energetic injections. New mid-infrared (10 micrometers or 30 THz) continuum observations are being carried out in Campinas, Brazil and El Leoncito, Argentina. They show quiescent bright areas in close association to Calcium plages in the visible and the active region magnetic features. Fast 30 THz brightenings are found associated to weak GOES soft X-rays bursts. The mid-IR fast bursts have a lifetime of several seconds, and are consistent to source sizes of few arc-seconds exhibiting temperature enhancements of the order of 10000 K.