A tour boat playing host to a bachelor party struck a rock in San Francisco Bay on Friday evening, prompting the evacuation of its 22 passengers and crew.

The boat, "The Neptune," had been chartered by the family of Matt Rice for his bachelor party and was about 20 minutes into the trip when it ventured inside a navigation buoy around 8:30 p.m. and struck a rock known as Little Alcatraz, according to KGO7 News.

No one was injured in the collision, which a crew member termed a navigation error. The impact ripped a pair of 1-foot holes in the hull, a crewwoman told KGO7, and attempts to pump water from the vessel were unsuccessful.

A pair of U.S. Coast Guard ships were dispatched to ferry the 18 male passengers and four crew members back to Pier 39 in San Francisco. The ship was reported to still be sinking at the crash site, near Alcatraz, late Friday.