Four more people have been found dead following a chocolate factory explosion in West Reading, Pennsylvania, last week, raising the death toll to seven, officials said Sunday night. All previously missing persons had been accounted for as of Sunday night.

Rescue crews worked overnight to inspect the rubble at the R.M. Palmer Company and discovered a fourth victim beneath debris early on Sunday morning, said West Reading police chief Wayne Holben said during a news conference earlier Sunday morning. The individual was pronounced dead at the scene.

"Crews are continuing their diligent effort in sifting through the debris in order to locate any additional individuals," the police chief said, adding that crews "are fully committed to this task" and "will do everything in our power to ensure that we bring closure to all those involved."

"I want to assure you all that we will not rest until every single person affected by this tragedy has been accounted for," said Holben. He could not provide an update about the woman who was pulled alive from the rubble on Saturday.