PHILADELPHIA, Pennsylvania (CNN) -- The explosion happened without warning around 4 o clock in the morning in West Chester, Pennsylvania.
FBI Agent Donald Bain sat in his car in a parking lot with two other agents. He was armed and wore a vest with a Kevlar vest. There was also a "flash-bang" grenade, a weapon that is nonlethal that gives a bright flash and deafening bang. It is used to disorient the enemy or suspects in situations of combat struggle.
The three agents - Bain, Thomas Scanzano and James Milligan - were waiting for developments on a kidnapping that had turned into a hostage stakeout.
That is when, Bain said, the flash-bang grenade exploded in his vest.
"The car was in flames," recalled Bain. "They told me later I was on fire. Smoke filled the car it was chaos. "
Scanzano recalls, "it was like being in combat. There was smoke and fire on the vehicle, and I knew that we were in trouble. "
An ambulance rushed the three agents to hospital.
Bain suffered severe bruises, a concussion and burns to the neck and ears. The three agents have said they have experienced loss of hearing.
It makes me crazy," says Scanzano. "I have difficulty sleeping. I have a very big headache. I have severe hearing impairment, and in every respect, I'm deaf in my left ear. "
