Three of the four people charged with setting two major fires in Norwich two years ago have now been sentenced in New London Superior Court.

Police said Matthew A. Markham, Laura MacDonald, Jonathan Ortiz and Nicholas Fauquet used gasoline to start fires at an occupied home at 7-9 Oak St. on March 26, 2012, and an unoccupied home at 11 Lake St. on March 29, 2012. The fires displaced more than two dozen people, caused hundreds of thousands of dollars in damages and resulted in two firefighters being injured.

Judge Hillary B. Strackbein on Tuesday sentenced Markham to five years in prison followed by three years of probation. He had pleaded guilty to two counts of second-degree arson and one count of tampering with a witness. While incarcerated on the arson charges, Markham had written to a cousin and offered her $100,000 to provide false information to his attorney, according to testimony in court.

Strackbein last week committed Laura MacDonald, 46, to the state’s hospital for the criminally insane for 37 years. MacDonald, who has a long history of mental illness and a fascination with fire-setting, was on probation for a previous arson conviction when she was charged with setting the Oak Street and Lake Street fires. Strackbein found MacDonald not guilty by reason of insanity in January following hearing at which West Hartford psychologist Rafael Gallegos testified that there is little or no likelihood her behavior will change and that she is in need of 24-hour supervision in a clinical treatment center “where she can be closely monitored to prevent her from engaging in dangerous and destructive behavior.”

Jonathan O. Ortiz, 25, was sentenced in February to seven years in prison for his role in the Oak Street and Lake Street fires and for setting fire to an occupied home at 124 Laurel Hill Ave. on March 22, 2012, and to a pickup truck at 500 West Main St. on March 1, 2012.

The case of Nicholas R. Fauquet is pending. He is due back in court on April 24.

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