16-year-old girl was seriously injured Friday when the horse she was riding at a farm in Groveland apparently got startled, rolled over and landed on top of her, town officials said.

Around 6:00 p.m., Groveland police and fire responded to a 911 call for a serious accident at a private horse farm and riding school at 104 King St., the fire and police department said in a statement.

Upon arrival , firefighters found the girl unresponsive. First responders provided emergency aid to her. A medical helicopter was called. She was taken by ambulance to a baseball field, where she was transferred to the helicopter.

She was flown to a Boston hospital. Her condition was not known late Friday night. The parents of the victim were promptly notified of the accident, officials said.

A West Newbury fire engine also responded to the scene and assisted at the landing zone for the helicopter, according to the statement.

“I would like to thank all rescuers who responded to this serious incident, including Groveland police and fire, West Newbury fire and Trinity medics,” said Groveland fire chief Robert Valentine. “Everyone involved worked together to quickly render aid to the patient and get her on board the medical helicopter efficiently.”