Two people are dead and at least nine people are missing after an explosion took place Friday afternoon at a chocolate factory in Pennsylvania.

The explosion took place at 4:57 p.m. at the R.M. Palmer Co. plant in West Reading, about 60 miles (96 km) northwest of Philadelphia.

It sent black smoke and debris into the air, video captured by Fox affiliate WTXF showed.

The blast destroyed a building at the facility and damaged a neighboring building.

The cause of the explosion is under investigation, West Reading Borough Police Department Chief of Police Wayne Holben told a press conference. He added that officials have ruled out a continuing danger to the area.

Holben confirmed that two people died and nine others were missing. Several others were injured, he added.

Residents were advised to avoid the area of the factory.

Eight people were taken to Reading Hospital Friday evening, said Tower Health spokeswoman Jessica Bezler.

She told The Associated Press via email that two people were admitted in fair condition, and five were being treated and would be released. One other patient was transferred to another facility, she said.

Hours following the blast, debris could be seen piled in the street, and at least one fire was still burning, video from NBC affiliate WGAL showed.

Berks County fire crews remained on the scene Friday night.

R.M. Palmer Company says on its website it has been making candy since 1948, specializing in seasonal items for Easter, Halloween, and Valentine’s Day. It employs 850 people.

The Associated Press and Reuters contributed to this report.