The number of confirmed deaths from a listeria outbreak grew to four as result of bacteria-infected cantaloupe from a Colorado farm that spread to 10 states in less than two weeks, federal health regulators said on Monday.

U.S. Centers for Disease Control and Prevention (CDC) announced last week that the death toll reached two from the outbreak, which officials say is linked to cantaloupe grown at Jensen Farms Inc of Holly, Colorado, 200 miles southeast of Denver.

But, health officials said Monday two more people had died in New Mexico, while one person died in Colorado and another in Oklahoma, putting the overall toll at four.

U.S. Food and Drug Administration (FDA) said that it found listeria monocytogenes on samples taken from equipment and cantaloupe at Jensen Farms' packing facility and in samples of its Rocky Ford brand cantaloupe taken from a Denver-area store.

CDC officials say deaths could rise to six if the CDC confirms two more deaths reported in New Mexico by the state's Department of Health.

A total of 35 people in 10 states have been infected since August 4, the CDC said on its website, an increase from the 22 illnesses the agency cited last week.

Jensen Farms, which had already been linked to the outbreak, recalled its Rocky Ford cantaloupes on September 14 in response to the listeria outbreak.

Consumers are being told not to eat the recalled cantaloupes shipped between July 29 and Sept. 10 to at least 17 states, the FDA said in a statement.

Listeria infection can be particularly dangerous for pregnant women, people over the age of 60 and those with compromised immune systems, health officials said.

Symptoms of the infection include fever and muscle aches, diarrhea, headaches, stiff neck and confusion, according to the CDC.

Antibiotics are effective in treating the infection in most cases.