A 19-year-old Norwich man charged with setting two major fires in the city in March 2012 has been accused of tampering with a witness.

Norwich police served Matthew Markham with an arrest warrant during his routine appearance Tuesday morning in New London Superior Court. Markham, who has been incarcerated since July 2012, allegedly wrote to his cousin, Kristina Baribeault of Uncasville, from the MacDougall-Walker Correctional Institution in May and offered her $750 to provide false information to Markham's attorney, Michael Jewell.

Markham and three others are accused of using gasoline to start fires at 7-9 Oak St. and 11 Lake St. that fire and police officials said caused more than half a million dollars in damages, put emergency responders at risk and displaced more than two dozen people.

Officer First Class Robert Smith and Detective Darren Powers investigated after the Department of Correction's Special Intelligence Unit intercepted the letter and contacted the state's attorney's office, according to the warrant.

Judge Hillary B. Strackbein read Markham his rights and set the bond at $5,000 for the new case. He is now being held in lieu of bonds totaling $600,600, and Jewell, his attorney, said Markham is "not going anywhere."

In the letter, Markham instructed his cousin to give a statement saying that Jonathan Ortiz, one of his co-defendants, had robbed him five times, broken his nose twice, cut him and set him on fire, according to the warrant affidavit. He also told her to say that he had been sleeping when the Lake Street fire occurred.

Markham told Baribeault he would give her $250 when he got out of prison and another $500 when he got his "papers straight," according to the affidavit.

During the original arson investigation, Ortiz had told police that Markham told him he and co-defendant Nicholas Fauquet set the fires because Fauquet was "mad about something."

Police interviewed Fauquet, who admitted that he and Markham had started the fire. But Markham denied his involvement and confronted Fauquet for "snitching" on him and was arrested for causing a disturbance, according to police.

Markham is due back in court on Oct. 21, when prosecutor David J. Smith is expected to make an offer to resolve the case short of trial.

k.florin@theday.com