Officials said the fumes were so bad, residents of the five units were forced to evacuate the building and find other places to stay. The building has been red-tagged, according to authorities.
The rock was described as covered with butyric and said the rock was thrown by a masked suspect sometime after 2:45 a.m.
The apartment in question is located at 429 Cypress Drive.
Police are not sure if the couple who live in the apartment where the rock was thrown were the suspect’s intended target.
Officials liken the fumes to pepper spray. The acid forms a cloud that makes it difficult to breathe and causes people who come in contact to have watery eyes as well as sore throats.
No residents required hospitalization.
Authorities could not say how long the clean-up would take and when residents could move back into their apartments.
On a garage door, police found a message in black spray paint that read, “Stalk someone else.”
They did not and could not say if the message was related to the attack.
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