SAN FRANCISCO (CBS SF) — A man who decided to explore the San Francisco sewer system and got lost Sunday morning escaped injury, fire officials said.

Firefighters were rescuing the man at 8:56 a.m. at 451 Berry St. in San Francisco’s Mission Bay neighborhood.

The man decided earlier Sunday morning to explore the sewer system and started yelling for help when he got lost.

A police officer heard him through a sewer grate and called firefighters who responded and rescued the man.

The rescue was complete by 9:03 a.m. and Berry Street reopened, according to fire officials.

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