A Waterville man pleaded guilty Friday in U.S. District Court in Bangor to being a felon in possession of ammunition, a charge that is related to an August 2014 Winthrop burglary.

Brian T. Mulkern, 35, is guilty of being in possession of 10 rounds of 9 mm ammunition, U.S. Attorney Thomas E. Delahanty II said in a news release. Mulkern allegedly stole the ammunition during an Aug. 26, 2014, Winthrop burglary in connection with which he was indicted by a Kennebec County grand jury in October.

Mulkern allegedly broke into a Holmes Road home and surprised a teenage girl, who called police and fled to a neighbor’s house..

Mulkern had been prohibited from possessing ammunition because of past felony convictions in Maine state courts for burglary, robbery and drug distribution, according to the release.

If Mulkern, who formerly lived in Winthrop, according to published reports, is found to be an armed career criminal because of his past drug trafficking and violent felony convictions, he would face a mandatory minimum of 15 years and a maximum term of life in prison, a $250,000 fine and five years of supervised release, the release said.

At his arraignment on the federal charges in March, Assistant U.S. Attorney Chris Ruge said in court documents, “The defendant was captured by local police at the scene of the burglary with the ammunition loaded into a magazine in his possession.

“The defendant stated that he had tried to also steal a corresponding handgun to trade for drugs out of state. The safe the handgun was in showed signs of his attempts to open it,” Ruge wrote.

The federal indictment lists a felony record that begins with robbery, burglary, theft and drug possession convictions in 2001, continues with an unlawful trafficking conviction in 2004, all in Cumberland County; a 2012 burglary in York County; and ends with a 2012 conviction for attempted heroin trafficking in Winthrop.

Mulkern was sentenced to 28 months in prison in February 2013 on the last conviction.

In the most recent Winthrop incident, Mulkern was indicted on burglary, theft and criminal mischief charges. Those charges have yet to be adjudicated.

The investigation was conducted by the Bureau of Alcohol, Tobacco, Firearms, and Explosives and the Winthrop Police Department.