An arson investigation is underway at an abandoned apartment building in West Philadelphia after a massive four-alarm fire that heavily damaged the building Saturday was found to be intentionally set.

Multiple Philadelphia fire trucks responded to a four-alarm blaze at an apartment building in West Philadelphia early Saturday morning. The building is on the corner of 48th and Locust streets.

PHA recently broke ground on the first phase of its Westpark Apartments redevelopment, which will include 327 affordable ...