WORCESTER, Mass. (AP) – Prosecutors have expanded their investigation into the death of an inmate at the Worcester County Jail, and the county sheriff said overcrowding may have been a contributing factor.

Daniel McMullen died at St. Vincent Hospital in Worcester on Wednesday, when his sister consented to removing him from life support. He fell into a coma days after he allegedly was beaten by his cellmate, Dennis Hadley, 49, during a fight over a deck of playing cards.

District Attorney John J. Conte told the Telegram & Gazette of Worcester that he is expanding the investigation into what happened. The probe will determine “whether or not … (jail personnel) fulfilled what they should have fulfilled, according to their duties.”

McMullen, jailed since November for a second drunk driving conviction, and Hadley, who was being held in lieu of bail on burglary charges, shouldn’t have been held in the same cell, Conte said, because it’s against the law to house a detainee and a jail inmate in the same cell.

The fight occurred on Feb. 3. McMullen received 13 stitches for a cut on his face. He was released but returned to the hospital seven hours later, complaining of continuing pain in his stomach and chest. He was diagnosed with internal bleeding and admitted to the hospital, where his condition deteriorated.

Hadley, who already faced assault and battery charges and was being held in isolation, is now likely to face more serious charges, Conte said.

Sheriff Guy W. Glodis sent a letter to Conte, calling for a second-degree murder charge against Hadley. Conte said a grand jury would determine the charges, if any.

Jeffrey Turco, deputy superintendent of the jail, said McMullen was transferred twice: soon after he first arrived at the jail and after his complaint about inmates urinating on his bed.

One problem is the jail is overcrowded, Turco said. There are 1,314 inmates, but the West Boylston facility has an intended capacity of only 822. On an average night shift – the shift in which the alleged beating occurred – there are only three correction officers guarding 120 inmates, he said.

McMullen was serving a six-month sentence.

The Telegram & Gazette reported that McMullen, who was gay, wrote letters to a friend complaining that other inmates were stealing his belongings. The letters gave no indication that he was harassed because he was gay, the newspaper reported.