Montgomery County Sheriff Eileen Whalon Behr said Friday that she was resigning to become director of police operations at Drexel University.

"This all came about rather quickly," she said. "It has been a very difficult decision to make."

The Lafayette Hill resident is the first woman to be the county's sheriff, having been appointed in 2011 after John P. Durante died.

She also was the first woman to be a police chief in the county. Behr was appointed chief of the Whitemarsh Township Police Department in 2003. - Carolyn Davis