A new cluster of Legionnaires' disease cases in the Bronx has city health officials on high alert.

Health Commissioner Dr. Mary Bassett announced that the city is looking into how seven Bronxites from Morris Park were infected and hospitalized with Legionella bacteria that afflicts victims with flu-like symptoms.

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At City Hall, Bassett told reporters that the Health Department tested all of the cooling towers in the Morris Park area over the weekend. She expects results back this week.

"It doesn't mean we know what the cause is," she said, "but they are geographically linked."

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Officials identified the cluster on Sept. 21. All the patients are between the ages of 45 and 75, and either live, work or have visited Morris Park recently. 

"We want to make sure people seek care early if they have symptoms," Bassett added.

Mayor Bill de Blasio also said all the towers were previously tested as a result of a new law to inspect cooling towers following the city's last bout with Legionnaires' disease in August.

At the time, 124 New Yorkers were linked to a previous cluster that officials sourced to a cooling tower at the Opera House Hotel in the South Bronx.

Twelve people died from the pneumonia-causing bacteria.

Basset cautioned that until the test results come back, the city can't link the latest out break to the cooling towers and may find other potential sources.