The 18-story Bronx building marked as the birthplace of hip-hop went up in flames early Tuesday morning.

Around 7 a.m., a fire broke out in the building that had more than 100 firefighters responding.

Firefighters say the fire started in an apartment on the seventh floor but spread to a second apartment one floor up after firefighters initially had difficulty putting it out.

One firefighter was injured and is expected to be OK.

It's unclear how the fire started.