An FBI agent fatally shot the victim of a kidnapping during a raid early Thursday at a Houston home, authorities said.

FBI spokeswoman Christina Garza said the agent shot the man shortly before 4 a.m. during an "operation" at the home. The man, whose name wasn't immediately released, died later at a hospital.

Police in Conroe, about 40 miles (64 kilometers) north of Houston, confirmed the man had been kidnapped and held for ransom.

"The system failed. Whether it was accidental or not, the man is not going home to his family," Conroe Police Chief Philip Dupuis said.

Two men and one woman are charged with aggravated kidnapping, police said. The men also are charged with aggravated robbery.

Police said the men broke into a home in Conroe and abducted the man. His 12-year-old son called police, who called the FBI for assistance.

The FBI followed cellphone signals to a motel near Houston, where two suspects — both of them men — were found. The suspects directed FBI agents and police officers to a house where another suspect — a woman — was located along with the man who was being held captive. Other people, including children, also were at the home, according to authorities.

It's unclear what led to the gunfire. Garza said the agent who fired the fatal shot is on administrative leave pending an investigation.