The platform, owned by Chevron Corp., evacuated all nonessential personnel.

"We received a report at 5:50 a.m. that the MV Monarch was taking on water," said Walter Shinn, a petty officer with the U.S. Coast Guard in Juneau.

The 166-foot-long vessel, which was carrying 35,000 to 38,000 gallons of diesel, had been pushed up against the platform, which is roughly 19 miles north of Nikiski on the west side of Cook Inlet near Tyonek.

There is an additional 20,000 gallons of diesel on the oil platform, Shinn said, and all fuel is fully contained at this time.

"There were seven people on board the vessel at the time of the incident.They managed to safely depart before it partially submerged," Shinn said. There were no major injuries reported and these seven people were flown by helicopter from the platform. An additional evacuation of 14 people on the platform was under way as a precautionary measure.

The Coast Guard already had dispatched a seven-person team from Anchorage to respond to the incident.

"A C-130 and H-65 (helicopters) from Kodiak were also set to respond, but high winds kept them grounded," Shinn said.

"A tug has also left Nikiski and is en route to assist in whatever way they can," he added. Officials do not know what caused the problem, but the Coast Guard was taking action to begin investigation.

OSK and Chevron did not immediately respond for comment on the incident.

Joseph Robertia is a reporter for the Peninsula Clarion.