FROSTPROOF, Fla. - A 46-year-old man charged with first-degree murder in the death of his aunt was found dead in the Polk County Jail of an apparent suicide, the Polk County Sheriff's Office said.

Pedro Vega Jr. was found hanging from a sheet in an isolation cell at 6:09 p.m. on Sunday during a routine inmate check, the agency said.

Vega was last seen standing upright by a detention deputy at 5:57 p.m. Inmates are checked every 15 minutes by a deputy, the agency said.

"When a detention deputy looked into his cell again at 6:09 p.m., Vega was seen slouching against a wall of the cell with what appeared to be a sheet around his neck," the agency said in a statement.

CPR was performed on Vega until paramedics arrived and transported him to Florida Hospital, where he was pronounced dead, the agency said.

"A search of Vega's cell revealed two plastic spoons with sharpened ends, which were apparently used to force the torn ends of the bed sheet into the small circular openings of the air return vent where they were tied," the agency said. "Deputies also found a noose in the pillowcase."

Vega was arrested on Aug. 30 for killing his aunt, Rosa Vega, who was stabbed 14 times, and critically stabbing his father, Pedro, who was stabbed at least 20 times. Following the stabbings, Vega went to a neighbor's house and shot the residents several times with a rifle stolen from his father's house, the sheriff's office said. One of the residents shot Vega in the hand.

Vega fled the area, but was later taken into custody by a Florida Highway Patrol trooper.

While being treated for the gunshot wound, Vega tried to escape from the hospital, the sheriff's office said.

Vega was booked into the Osceola County Jail on Sept. 1, then transferred to Polk County on Sept. 2.

An investigation into Vega's death is ongoing.