San Antonio Police on Wednesday made a third arrest in connection with the murder of pregnant teenager Savanah Soto and her boyfriend Mathew Guerra. Myrta Romanos, 47, now faces three felony charges, including altering or destroying a corpse, abuse of a corpse and tampering with evidence, authorities said. She is the long-term girlfriend of Ramon Preciado, 54, and acting stepmother of Christopher Preciado, 19, according to police.