The blaze broke out in three two-story homes just after 6 a.m. Sunday on the 1200 block of Orion Drive, 6abc says.
A lack of nearby hydrants hampered efforts to extinguish the fire, officials told 6abc. Fire crews were on scene for approximately three hours, according to the Hartsville Fire Company.
Past fires caused by squatters have damaged the homes in previous years, authorities told 6abc.
No injuries were reported. The cause of the fire is under investigation by the Warminster Township Fire Marshal.
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