BANGOR, Maine — Nathaneal Nightingale, 31, of Burlington, entered not guilty pleas on Wednesday to two counts of intentional or knowing murder in the shooting deaths of a Webster Plantation couple found dead in their trailer in November.

Michael Miller and Valerie Miller, both 47, were found in their Tucker Ridge Road home on Nov. 28, 2009. Both died of small-caliber gunshot wounds to the head, according to the state medical examiner’s office.

In addition to pleading not guilty, Nightingale answered two questions during his arraignment before Penobscot County Superior Court Justice Michaela Murphy, saying he understood the charges against him and the possible penalties.

If convicted, he faces a minimum sentence of 25 years in prison, and a maximum of life without parole, for each of the two counts, she said.

“The counts on there could run concurrently or consecutively,” Murphy said.

The judge then set a deadline of 60 days for motions. The accused man’s attorney, Jeffrey Silverstein, said he didn’t expect that to be a problem, but kept the door open for a possible extension, if needed.

When the investigation into the Millers’ deaths began, Nightingale initially provided investigators with a composite sketch of a female suspect who turned out not to exist, according to police.

After his arrest, which occurred about two weeks after the shootings, Nightingale told police he shot the husband and wife, who were his friends, after a botched robbery, according to a state police affidavit filed with the court.

Nightingale was indicted by the Penobscot County grand jury on Dec. 28, 2009. His original January arraignment was postponed until Wednesday’s court proceedings, because Silverstein was out of town.

Nightingale will be held without bail at Penobscot County Jail in Bangor until his trial date, which was not set.