Parents of Kingsway Regional High School students last night reacted with shock and dismay over the arrest of a 28-year-old physical-education teacher and coach on charges she was having a sexual relationship with a 17-year-old female student.

Erica Umosella of Yellow Wood Court in Glassboro was charged Wednesday with aggravated sexual assault, official misconduct, and aggravated criminal sexual contact, the Gloucester County Prosecutor's Office said yesterday. She posted $50,000 bail and was released.

The student was a member of the Woolwich Township school's field hockey team, which Umosella coached, officials said.

In a district still reeling from the death of a marching-band member three weeks ago, "we don't need any more bad news," said Bob Kurek, whose daughter Lauren is a Kingsway senior.

"It's just sad," he said of the arrest and allegations.

Jon Sanger, whose daughter Melissa is also a senior at the school, said word of Umosella's arrest was spreading via "e-mails and text messages."

He said Umosella "is a good person."

The sexual contact allegedly occurred during the last month at Umosella's home. No other alleged victims have come forward, officials said.

The investigation began after Kingsway Superintendent Ave Altersitz told authorities about an anonymous letter, said Bernie Weisenfeld, spokesman for the Prosecutor's Office.

The school suspended Umosella as a teacher and as softball and field-hockey coach. She has worked in Kingsway since September 2003. The Prosecutor's Office and police in Glassboro and Woolwich are investigating.

Contact staff writer Diane Mastrull at 610-313-8095 or dmastrull@phillynews.com.