SIGNAL HILL, CA — A fired employee shot and critically wounded three people at a menu printing plant this morning before killing himself as a SWAT team entered the building, authorities said.

The shooting occurred at Kenyon Press about 9 a.m., said Los Angeles County Fire Department Inspector Ron Haralson. Haralson said three people were critically wounded.

"The shooter, a fired employee, died of a self-inflicted gunshot wound when SWAT entered," said Valarie Carlomagno, secretary to the police chief.

The names of the gunman and victims weren't yet available. The shooter appeared to be about 60 and the victims, all men, are all in their 50s, Carlomagno said.

The SWAT operation was conducted by a team from neighboring Long Beach.

Kenyon Press, which makes custom designed menus, has customer service personnel, copywriters, designers, illustrators, proofreaders, prepress, press and bindery/manufacturing workers. Its clientele includes Las Vegas casinos and hotel chains, according to its Web site.

Signal Hill, a city of about 11,000, is 20 miles south of Los Angeles, adjacent to Long Beach.