By CBS13 Staff

SACRAMENTO (CBS13) — Firefighters have doused a fire that prompted a three-alarm response near Midtown Sacramento early Thursday morning.

The scene was at a vacant building near S and 15th streets.

Sacramento Fire says their crews responded just after 4 a.m. Three-alarms were called as firefighters initially found it difficult to get to the flames due to a partition in the building.

Eventually, firefighters had to go in through the roof. The fire is now out.

There were initial reports of someone possibly being inside, firefighters say, but a search of the building came up empty.

More from CBS Sacramento:

Exactly what started the fire is now under investigation.