Philadelphia Academy Charter School founder Brien N. Gardiner, under federal investigation in connection with his management of the school, committed suicide yesterday afternoon, Lower Moreland police said.

Township Detective John Pasqueal said it appeared that Gardiner, 64, died of a self-inflicted gunshot in the parking lot of the Bethayres Train station about 1:20 p.m. He was not in a car and died at the scene, Pasqueal said.

The train station is about a mile from Gardiner's home on Kent Road in Huntingdon Valley.

Pasqueal said that police were withholding details, including whether Gardiner left a suicide note.

Gardiner founded Philadelphia Academy in Northeast Philadelphia in 1999; he also opened the Northwood Academy Charter School in 2005, and at one time was chief executive of both charters.

He later became a consultant at Philadelphia Academy. That contract was terminated last spring, after The Inquirer disclosed that the Philadelphia School District inspector general was investigating allegations of financial mismanagement, nepotism, and conflicts of interest at the school.

A federal criminal investigation of Gardiner and of former chief executive officer Kevin M. O'Shea, who had replaced Gardiner as head of the school, was launched later last spring.

There have been no indictments or arrests. Patricia Hartman, a spokeswoman for the U.S. Attorney's Office, declined to comment, as did Derek A. Cohen, an assistant U.S. attorney who is directing the probe.

Sources with knowledge of the investigation said indictments were imminent.

In July, an internal report submitted to the board of the school by former federal prosecutor Henry E. Hockeimer and other lawyers at Ballard, Spahr, Andrews & Ingersoll L.L.P., alleged that Gardiner and O'Shea had systematically looted the school for personal gain.

The report said that more than $700,000 was missing from a school account and it cited "substantial evidence of wrongdoing" by Gardiner, a former public-school principal, and O'Shea, a former police officer.

Before founding the charter, Gardiner was a popular principal at Farrell Elementary School in the Northeast. He was so well-regarded that several Farrell staff members and many parents followed him to Philadelphia Academy.

Because of his history in the district, he had long-standing, close relationships with many district officials.

Last night, members of the charter-school community expressed shock and sorrow over Gardiner's death and recalled him as a trailblazer.

"We are extending our prayers to his family," said Lawrence Jones, president of the Pennsylvania Coalition of Charter Schools. "Brien was a pioneer in the charter community."

Through his work, Jones said, Gardiner contributed to the lives of countless children in the school district and in charter schools.

David Hardy, CEO of the charter school Boys Latin of Philadelphia, said Gardiner provided advice and help to anyone who wanted to start a charter and to operators who wanted to improve their schools

"This is a real tragedy," Hardy said. "I hope that people can remember the great things he did."

Contact staff writer Martha Woodall at 215-854-2789 or martha.woodall@phillynews.com.