A Lynn woman who allegedly participated in a scheme to extort money from strangers by telling them their loved ones had been kidnapped may face additional charges, according to Suffolk County District Attorney Daniel F. Conley.Mary R. Lozada, 34, was held on $5,000 cash bail on Friday following her arraignment in Roxbury District Court on two counts each of extortion by threat of injury, larceny over $250 and conspiracy to commit larceny. Judge Pamela Dashiell also ordered Lozada to stay away from the Western Union locations she allegedly visited to collect extortion payoffs.According to District Attorney Benjamin Goldberger of Conley’s Special Prosecutions Unit, the charges reflect two of possibly 30 separate incidents in which Lozada allegedly participated. He also said two of the phones used in the alleged offenses have been linked to eight other extortion calls, of which only one was a success.The first scheme Lozada has been charged with occurred on June 8. A Jamaica Plain woman received a phone call from a Spanish-speaking male claiming to have her son. The man threatened to kill him if she did not wire $1,500 to his captors. The victim told Boston Police the caller settled for $700, which was wired to Amarilis Cordova via Western Union. The woman’s son had not been kidnapped, though he was at a friend’s house.The second scheme occurred on June 9, when a Dorchester man also received a call from a male speaking in Spanish. The caller acted as a friend of the victim’s son, saying the son was being held against his will and wouldn’t be released until his captors were wired $1,000. The ransom was negotiated down to $500 which was also wired to Amarilis Cordova through Western Union. The victim later found his son had never been in danger.Lozada allegedly collected the money from the first call at 43 Broad St. and the second at 35 Washington St., both Lynn addresses. Her presence was confirmed by photographic array and surveillance images. Prosecutors said the incidents were similar to others that have taken place in Boston, Chelsea, Revere and Lynn throughout the spring. Most attempts were unsuccessful, but some victims did wire money to the caller. These cases remain under investigation by police and prosecutors in Suffolk and Essex Counties.Investigators urged anyone who has received such calls to contact their local police departments.Lozada was represented Friday by Norm Orban, who is supervised by the Committee for Public Counsel Services.