PASADENA – A balcony walkway in a two-story building partially collapsed Thursday, briefly blocking the door to a first-floor doctor’s office but causing no injuries, authorities said. Eight people were temporarily stuck in the office. “The ceiling was so low the people trapped inside couldn’t open the door. Now it’s safe,” said fire Capt. Felipe Niquete. “We opened the door for them so they could get out.” More than 100 tenants of the downtown Park Center office building at 221 E. Walnut St. were evacuated after the interior atrium balcony collapsed around 10 a.m., said Fire Department spokeswoman Lisa Derderian. The building has a plant-filled interior courtyard. Veronica Martinez, a medical assistant in the doctor’s office, said construction crews had been working in the building. “Then we kind of heard a bunch of commotion outside,” she said. “Our door wouldn’t open.” Martinez and her colleagues – a nurse practitioner and endocrinologist Dr. Dorothea E. Spambalg – had five patients in the office and continued to work. “I don’t know. Work ethic,” shrugged Martinez. She also called other patients to tell them not to come in. Firefighters shored up the slumping balcony with wooden beams. The building was closed until further notice and the investigation was turned over to building inspectors. “Construction is more than likely the cause,” Derderian said.