Thousands of people, mostly in the Santa Rosa area, remained without electricity or gas Thursday as a small army of PG&E workers continued to restore service to fire-stricken areas.

PG&E crews have strung line and restored service to about 7,000 customers since the deadly firestorm struck late Sunday night, said Deanna Contreras, a utility spokeswoman, but some 44,000 additional customers are still without power.

Gas service to 31,000 customers in the Santa Rosa and Windsor areas was shut off by PG&E in order to safely repair damage caused by the fires, and 28,000 customers were still without gas Thursday, she said.

Windsor is not in the fire area, but gas flow had to be shut down in pipes even outside the damaged area so crews could safely make repairs, Contreras said.

Starting Wednesday, the utility had 250 gas service technicians at work, including those making door-to-door checks with customers as late as 11 p.m.

Repairs are slowed by the necessity to make sure areas are safe before crews go in, Contreras said.

PG&E has deployed more than 1,500 workers, including repair crew members and administrators, staged at a Rohnert Park base camp, and reinforcements are expected, she said.

Contreras said she could not offer a timetable for restoring service to all customers.

Meanwhile, AT&T has restored more than 99 percent of cellphone service throughout a Northern California region that includes Sonoma, Mendocino, Lake and Napa counties, said Kate Ijams, a company spokeswoman.

Crews have been working around the clock, but some areas remain inaccessible or too dangerous to enter, including some areas north of Santa Rosa, Ijams said in a press release.

Mobile cell sites have been deployed to areas where regular sites have burned or cannot be reached, including part of Santa Rosa, Calistoga and Yountville.

AT&T teams and special equipment, such as satellite links and cell sites mounted on trucks, have afforded some communities and first responders access to voice calls, texting and wireless internet, Ijams said.

Ijams said she was unable to report the number of cell towers that had been knocked out by the fires.

AT&T Community Response Teams are at local shelters providing WiFi, charging stations, phones for use and other services.

The shelters are at Elsie Allen High School, Sonoma County Fairgrounds and Veterans Memorial Building in Santa Rosa and at Napa Valley College.

You can reach Staff Writer Guy Kovner at 707-521-5457 or On Twitter @guykovner.