CALAVERAS COUNTY, Calif. — 4:40 p.m. update:

The Calaveras County Sheriff's Office is still attempting to find the pilot of a plane that crashed in Calaveras County Lake.

The plane is completely submerged and a dive team is at the location.

Original story:

A plane has crashed into a lake in Calaveras County, according to the Tuolumne County Sheriff's Office.

The plane crashed into Lake Tulloch in Copperopolis on Sunday around 11:39 a.m. Eye witnesses reported seeing the plane hit power lines before entering the water nose first. They said the plane quickly sunk near the Poker Flat area of the lake, according to a tweet by the sheriff's office. 

Cal Fire said the plane crashed into 50 to 70 feet of water.

Authorities said the pilot of the plane was the only person on board. 

The Calaveras County Sheriff's Office said Cal Fire's Marine Safety Unit, and the Tuolumne County Sheriff's Office and its boating division are assisting them with the investigation.

"Please avoid the area so that emergency crews can make access quickly. Power is out in the area," said a Facebook post from the Tuolumne County Sheriff's Office.

There is no information regarding the cause of the crash at this time.

This is a developing story. We will have more information as it becomes available.

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