Mt Diablo Fire by Tonya White for websiteTemperatures nearing 100 degrees coupled with a dry winter, off-shore winds and dense, bone-dry fuel set the stage for the biggest Mt. Diablo wildfire in 36 years.

The fire started at the mercury mines on Morgan Territory Road on Sunday around 1:30 p.m. The cause is officially “under investigation,” but neighbors say it was sparked by someone target shooting.

By 3 p.m. on Sunday, the fire, dubbed the “Morgan Fire,” had burned over 800 acres, threatening homes and power lines and forcing evacuations from Oak Hill Lane and Curry Canyon.

AirCloud Communications which provides internet service to the Morgan Territory and Marsh Creek areas, lost electrical power to their communication equipment on North Peak around 11 p.m. Sunday night

With the fire spreading fast, the critical issue was getting the horses and other large animals out of the area. By late Sunday afternoon, SUVs and trucks pulling horse trailers joined the steady stream of fire trucks, bulldozers and heavy equipment lining Morgan Territory Road.

The steep, rugged and densely wooded east side of Mt. Diablo presented huge challenges to fire fighters and equipment trying to gain access. The fire raged out of control through Sunday night, growing to 2000 acres by Monday morning. At 10 a.m., the fire was only 10 percent contained according to East County Fire Chief Hugh Henderson.

The fire continued to grow Monday, spreading south toward San Ramon with the heaviest activity on the east side of Mt. Diablo above Curry Canyon and on the north edge of North Peak above Russelmann Road.

According to CalFire Public Information Officer, Dave Shew, more than 800 personnel from CalFire, CCCFPD, ECFPD and dozen other local fire districts were on scene. Two DC 10s were on the fire until late afternoon, when they were called to another major fire burning near Shasta.

A Red Cross evacuation center set up at the Clayton Library drew mostly government officials and locals looking for information or just to connect with others. Most of the evacuees found lodging with friends or relatives in the area.

Curry Creek resident Virginia Fraser came with her cat, Emma. She saw the black smoke and flames around 2 p.m. on Sunday and alerted her neighbors before leaving. “I thought it’d be a nice quiet day, sitting there reading the Sunday papers,” she said. “Then, boom – all this.”

As of 3 p.m. Monday, according to the CalFire incident website, the fire had burned 3,718 acres and threatened 100 homes and was still only 20 percent contained.

Monday night when this paper went to press at midnight, the fire was still active. Earlier in the evening, flames flared up on Morgan Territory Road near the origin, jumping the road at one point and causing more evacuations.

At press time, the CalFire site had not been updated since early in the day Monday. The CalFire media information office had no map showing the boundaries of the fire, active areas or containment lines, leaving residents in the fire zone dependent on local blog sites and social media for critical information.

The last huge fire on the mountain was in 1977, when lightning sparked a fire that burned 6000 acres.