The fire was reported about 9:45 a.m. at the vacant Tree Line Park Apartments at 901 W. McWilliams Ave., near H Street and Bonanza Road, the Las Vegas Fire Department said in a statement.
Another blaze at the location occurred about 10 a.m. Friday.
On Monday, one building had heavy flames and smoke, which firefighters brought under control in about 20 minutes, the department said. About half of the building was damaged.
A damage estimate was not immediately available; no injuries were reported.
The fire’s cause is under investigation, though the Las Vegas Fire Department suggested the fire may have been caused by squatters.
Contact Bianca Cseke at firstname.lastname@example.org or 702-383-0381. Follow @biancacseke1 on Twitter.36.178714,-115.1561757