According to details, the company's industrial park in Chicago, Illinois, entered an
armed man at noon, when the security forces arrived at the scene, the accused started firing blindly after seeing the police.
The foreign news agency said 5 policemen were killed on the spot when the attacker was shot dead, while several others including security personnel were injured in bullets.
The police identified the accused as a 45-year-old Gray Martin employee's employee.
The police have avoided speculation about the purpose of the attack, but according to the news agency, the family members say they were suffering from intense mental stress.
According to the foreign news agency, the attacker was also killed during a shootout in police and assault.
The administration took a high alert in the area, while specially scheduled for school students in West Chicago continued to be in school.
The foreign news agency said the police immediately started investigating the area surrounded by the area.
The attack was very bad and terrible, today's day proved to be very bad for American citizens, "said Illinois's Senator Tommy Dickter.
White House spokeswoman Sarah Sander has briefed US President Donald Trump about the Chicago invasion, but there was no statement of President Trump.