The Coast Guard late Tuesday evening said an initial review of internal communications aboard the tanker Overseas Reymar show the crew was warned just before the huge ship scraped a fender protecting the base of a tower on the Bay Bridge.

The tanker has been ordered to anchor north of the span indefinitely as the investigation into the collision continues.

In the announcement late Tuesday, the U.S. Coast Guard revealed that before the 750-foot oil tanker struck a tower of the Bay Bridge Monday morning, the individuals monitoring its travels warned the crew of danger.

According to information released by the Coast Guard, Vessel Traffic Service on Yerba Buena Island – the organization tasked with helping ships navigate San Francisco Bay waters safely – was in communication with the Overseas Reymar and alerted the ship to the hazard.

Officials did not say whether the pilot had time to react to that communication.

"The captain of the vessels themselves are responsible for the safe navigation of their own vessel," said U.S. Coast Guard Lt. Commader Rick Foster.

Bar pilot Guy Kleess is no stranger to San Francisco Bay, having guided large vessels through the tricky waters since 2005.

The Coast Guard completed its interview with Kleess and crew members Tuesday and inspected the ship to evaluate the damage and determine if equipment on board was working properly.

"They'll have possibly two radars," said Lt. Foster. "They'll have electronic GPS. They'll have navigators, manually plotting the course."

Visibility at the time was a quarter of a mile, but KTVU has learned there are no sight restrictions for passing under the bay bridge.

After the Cosco Busan disaster five years ago, new rules were adopted to prevent large ships from sailing when visibility is less than a half a mile, but only in nine so-called critical maneuvering areas.

The busy Bay Bridge is not one of those areas.

State records KTVU obtained showed Kleess has had three prior accidents, but all of the accidents were considered minor.

Kleess was ordered to receive extra training after having two incidents in just three days during August of 2009.

An investigator with the National Transportation Safety Board arrived Tuesday night and will be examining the ship Wednesday.