Naperville townhouse left uninhabitable by fire

A Naperville townhouse was left uninhabitable after an early morning fire Tuesday that damaged two other units as well.

Naperville firefighters were dispatched to the 1600 block of Mulligan Drive about 1:45 a.m. for an activated fire alarm.

Residents of the unit also called dispatchers to report a car in the attached garage and a car in the driveway were on fire.

The fire spread to two other units, one of which was vacant. Both were deemed habitable.

Paramedics treated one person at the scene.

The cause of the fire remains under investigation.

No damage estimate was reported.