Police official gives an update
A man who opened fire on colleagues at a plastics factory in Kentucky warned his girlfriend two hours before that he would kill his boss, police said.
Wesley Higdon, 25, shot dead five fellow workers and injured another before turning the handgun on himself.
He opened fire at the Atlantis Plastics factory in Henderson city after arguing with a male supervisor.
Higdon killed his 30-year-old supervisor, two other male workers and two females, police told the BBC.
A sixth victim, a woman, was in a stable condition in hospital.
The 22-year-old was being treated at St Mary's Hospital in Evansville, Indiana, Det Preston Herndon of Henderson's police force told BBC News.
Higdon, a night-shift worker, had a row with his supervisor about wearing safety goggles on Tuesday night, then called his girlfriend and said he was going to kill him, police said.
Higdon shot the supervisor outside the plant before re-entering the building to open fire on other colleagues, Det Herndon told the BBC.
"We're still piecing together events but we believe the gunman had an altercation with a supervisor and went out to his vehicle to retrieve a firearm," he said.
"We believe he then had another altercation outside with the supervisor and opened fire.
"He then went into the building to a break room with lunch tables set up where other colleagues were and continued his shooting spree."
Atlantis Plastics chief executive officer Bud Philbrook told the Associated Press news agency that the killings were a "total shock".
The rampage happened at about 0015 local time (0415 GMT) on Wednesday.
Staff at the plant, which employs about 150 people and makes refrigerator parts, were sent home.