New York (PTI): The gunman, who shot dead 13 people and then killed himself in a small town of Binghamton, about 250 km from New York, was depressed and angry over losing his job and about his poor English skills, media reports said.

"People degraded and disrespected" the gunman over his poor English, police chief Joseph Zikuski told NBC television.

The shooter had worked in Binghamton for Shop-Vac, which closed in November, Mr. Zikuski said.

Police are still not sure of the motive, but family and friends indicated that Wong was upset about losing a job at the company Shop-Vac and felt he was "being degraded" because of his inability to speak English well, he said.

Because Wong had been wearing body armour at the time of the shooting, police think he may have anticipated an altercation with them, though he evidently chose suicide instead, he added.

The man, believed to be 42-year-old Vietnamese immigrant Jiverly Voong, was angry about his language issues and his lack of employment, Mayor Matthew Ryan told ABC.

The mayor said that the gunman "had lost a job recently and was somewhat angry".

"He had language issues, didn't speak English that well, and was really concerned about his employment situation," Mr. Ryan said.