An apartment building was evacuated and a portion of a busy thoroughfare was shut down for a hazardous materials investigation near the Caltech campus Monday morning.
The initial call came in around 6:15 a.m. Monday morning when a passerby saw a man dressed in a full hazmat suit mixing chemicals on his balcony, prompting them to alert police, the Pasadena Fire Department said.
The apartment building is located in the 900 block of Del Mar Boulevard between Mentor Avenue and Wilson Avenue, adjacent to the Caltech campus. Pasadena fire officials told KTLA that it is not student housing, but some students do live there.
A total of 18 units were evacuated, officials confirmed, with 24 residents being temporarily displaced.
Video from Sky5 shows what appears to be an impromptu lab setup on the ground floor porch of one of the apartments. It is unclear what chemicals may be present. 
Video from Sky5 shows what appears to be an impromptu lab setup on the ground floor porch of one of the apartments. It is unclear what chemicals may be present. 
Video from Sky5 shows what appears to be an impromptu lab setup on the ground floor porch of one of the apartments. It is unclear what chemicals may be present.
Video from Sky5 shows what appears to be an impromptu lab setup on the ground floor porch of one of the apartments.
“Burbank and Glendale hazmat teams entered the apartment, identified multiple chemicals on the premises, but no release of hazardous products was detected,” a statement from the City of Pasadena said. “Pasadena investigators and Los Angeles County Health hazmat teams coordinated the removal of the chemical contents and all occupants were allowed to reoccupy the residence.”
Photos released by officials show a closer look at the DIY science lab, complete with beakers, chemicals and a clear whiteboard with equations on it. (City of Pasadena) 
Photos released by officials show a closer look at the DIY science lab, complete with beakers, chemicals and a clear whiteboard with equations on it. (City of Pasadena) 
Photos released by officials show a closer look at the DIY science lab, complete with beakers, chemicals and a clear whiteboard with equations on it. (City of Pasadena)
Photos released by officials show a closer look at the DIY science lab, complete with beakers, chemicals and a clear whiteboard with equations on it.
A man was taken into custody by Pasadena police for questioning, law enforcement officials said.
Officials remained on scene and the area remained blocked off through midafternoon on Monday. A private company conducted the cleanup and removed the hazardous materials, police said.
No injuries or medical complaints were reported.
