Michelle Troconis, the girlfriend of Fotis Dulos, was arrested Thursday on an additional charge of tampering with evidence in the Jennifer Dulos case.

Troconis turned herself in at Troop G in Bridgeport where she was processed by state police, officials say. She has since posted $100,000 bond and released from custody, and is expected to plead not guilty.

Her arraignment is slated for Sept. 18 in Norwalk Superior Court.

She has been cooperating with police, disclosing incriminating details about her boyfriend and his alleged connection to the disappearance of Jennifer Dulos.

RELATED: A closer look at Fotis Dulos' arrest warrant

According to the arrest warrant released Thursday, Troconis met with police on Aug. 13 for a third recorded interview where she admitted Fotis Dulos left his phone at his office in Farmington the day Jennifer Dulos disappeared.

The warrant also says she told police she did not know where Fotis Dulos was during the early hours of May 24, when Jennifer Dulos went missing. Troconis admitted she did not see him between 6:40 a.m. and 12 p.m. that day.

Troconis did identify herself on surveillance video with Fotis Dulos discarding bags into trash bins along Albany Avenue in Hartford. Police say those bags contained Jennifer Dulos' DNA.

In a statement after her arrest, Dulos' attorney Norm Pattis said, "Our hearts go out to Ms. Troconis. We are confident that she will, in the end, tell the truth at trial. The state is a terrifying enemy, but a clean conscience is a powerful ally."

The New Canaan Police Department posted to Twitter Thursday afternoon, "Justice for Jennifer! We will not rest until she is found and justice is served."

Fotis Dulos was also re-arrested Wednesday, and also faces charges in connection to his estranged wife's disappearance.