The U.S. Coast Guard was continuing to investigate a collision on Saturday between a Golden Gate Ferry and a 22-foot motorboat, a spokesman said Sunday.

Investigators were trying to determine who was at fault in the crash on San Francisco Bay that sent two people to the hospital at around 4 p.m., Coast Guard Lt. Mark Leahey said.

According to Golden Gate Transit spokeswoman Mary Currie, the motorboat was traveling at high speed when it collided with the MS San Francisco, which was about 10 minutes into its 30-minute trip from Sausalito to the Ferry Building in San Francisco.

The crash took the ferry out of service, though it was able to return to port in Sausalito on its own.

All five crewmembers aboard were expected to be drug tested and placed on administrative leave pending the results of the investigation, as per standard procedure in such incidents, according to Currie.

Golden Gate Ferry service was running on a normal weekend schedule Sunday, Currie said.