CHICAGO (CBS)– One person is in custody and being questioned following an investigation of a “suspicious object” that was dropped off in a mailbox in the Logan Square neighborhood Wednesday morning.

According to police, the incident has been cleared and the package was “not determined to be incendiary.”

Police told CBS 2 the package is potentially narcotics related.

Chicago police responded to the area of Fullerton and Central Park avenues.

Fullerton Avenue was blocked off from Kimball to Monticello avenues, police said.

Central Park Avenue was also blocked as police investigated.

Venus Rivera was at doctor’s office with her son, when they evacuated the building around 11:15 a.m. She said her car is stuck in the parking lot while police work to investigate the suspicious package.

“They found an unidentified object in the street, and they’re trying to identify it to see if it’s a bomb or anything, considering it’s 9/11. Trying to do their jobs,” she said.

Charges are pending.

This is developing story.