SAN FRANCISCO (CBS SF) — Work crews inspected a massive sinkhole early Friday that created a gaping hole in a street in San Francisco’s posh Pacific Heights neighborhood.

READ MORE: Sinkhole Repaired In SF Pacific Heights; Repaving Monday

READ MORE: San José School District Secures Vaccine for Entire Workforce

According to the San Francisco Public Utilities Commission, a 17-foot by 22-foot area of Sacramento Street collapsed between Lyon and Baker streets around 5 p.m. Thursday.

Road crews were nearby filling in an indentation in the street when the collapse occurred. No injuries were reported.

READ MORE: Golden Gate Fields Races to Make Up for Missed Vaccine Appointments

The incident appears to have been caused by a sewer main break at the same location, although the cause of the break is not yet known. Water and sewer service has not been affected, however.

Sacramento Street was closed between Lyon and Baker. Muni lines weren’t affected.

Although it is not clear what caused the break, Florencia Prada, a spokeswoman for SF PUC told KPIX “We do know that this particular pipe is actually quite older — a hundred years old.”

MORE NEWS: Study Shows Stockton Universal Basic Income Experiment Led to Increased Employment

TM and © Copyright 2016 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2016 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Bay City News Service contributed to this report.