PHILADELPHIA - A woman who had just been suspended from her job and escorted from a Kraft Foods Inc facility returned with a handgun and opened fire, killing two people and critically injuring a third before being taken into custody about an hour later, police said.

The shooting happened on Thursday in the city's northeast section inside a plant of the nation's largest food manufacturer, whose products include Oreo cookies, Lieutenant Frank Vanore said.

Kraft said in a statement that in addition to the three employees who were shot, a contract worker sustained a less serious injury, but it did not elaborate.