WASHINGTON – A defective water heater caused a carbon monoxide scare in Georgetown and sent one woman to the hospital Friday.

The D.C. Fire and EMS Department tells WTOP 17 people had to be checked out at the scene after carbon monoxide was detected in the 1200 block of 33rd Street in Northwest.

The department responded to several apartments on that block early Friday.

It’s the third carbon monoxide incident in the District this week.

On Thursday, three people became ill after a carbon monoxide leak near Dupont Circle. One of the victims was in serious condition.

A third incident occurred in Georgetown on Tuesday.

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