The fire marshal has opened an investigation into an apartment fire that entrapped multiple people Friday in Mount Laurel.

Officials say the flames broke out around 5 a.m. in the 500 block of Fellowship Road.

Crews found the fire in the ceiling of the first floor, under the second floor’s balcony.

The tenants managed to escape the flames soon after firefighters arrived at the scene.

No injuries were reported, according to authorities.

The cause of the blaze remains under investigation.