Allentown, PA: Pennsylvania Town Rocked By Explosion (VIDEO)

A natural gas explosion rocked the Eastern Pennsylvania city of Allentown last night, leveling two houses and leaving behind fires that burned throughout the night.

The city, located in Lehigh County, has a population of about 111,000. The explosion, which occurred in a mainly residential downtown section of Allentown, killed at least one person, according to the AP. Five other individuals remain unaccounted for.

The 500 to 600 residents that were evacuated after the 10:45 p.m. explosion have since been allowed to return to their homes.