HELENA, Mont. — The former Navy SEAL who says he fired the shots that killed Osama bin Laden was arrested Friday on a drunken driving charge after police found him asleep in a car parked at a convenience store in his Montana hometown.

Customers at the store in Butte called police to report a sleeping man behind the wheel of the running car around 2:30 a.m., Butte-Silver Bow County Undersheriff George Skuletich said. The officer who responded woke the man up, identified him as Robert O’Neill and noticed odd behavior.

“He was confused. His actions were consistent with somebody who might be under the influence of something,” Skuletich said.

O’Neill denied drinking, gave different stories about where he had been and at one point told the officers he had taken prescription medication to help him sleep, Skuletich said.

O’Neill failed a field sobriety test and would not perform others. The officers brought him to jail, where he refused a test to determine his blood alcohol level. At that point, he was charged with driving under the influence, which is a misdemeanor, Skuletich said.

Jail records show O’Neill was released at 4:26 a.m. after posting a $685 bond. It is his first arrest.

O’Neill denied that he was intoxicated and thanked police for their professionalism and courtesy.

“The facts are that I took a prescribed sleep aid to help with long-standing severe insomnia,” he said in a statement released Friday through a public relations firm. “While the timing was bad and I highly regret this decision, I am innocent of the charge and have entered a plea of not guilty.

“I am confident I will soon be cleared of this matter,” he said.

O’Neill began publicly discussing his role in the 2011 bin Laden raid two years ago. He told The Associated Press in a 2014 interview that the American public had a right to know more details about the killing of the al-Qaida leader.

Pentagon officials previously said it is not clear whose shots killed bin Laden.

O’Neill has made numerous speeches across the country since 2014.

O’Neill, who joined the Navy in 1995, participated in the 2009 rescue of the captain of a merchant ship taken hostage by Somali pirates, a mission that was the subject of the Tom Hanks movie “Captain Phillips.”

He also helped rescue the survivor of a four-man team attacked in 2005 while tracking a Taliban leader in Afghanistan, which was featured in the 2013 film “Lone Survivor.”