More than 1,300 people from Louisiana and Mississippi have come to the Washington region since Hurricane Katrina upended their lives nearly two weeks ago, according to local government officials and the American Red Cross.

Authorities said they suspect that the actual number is higher because many evacuees are staying with families or have yet to enter the social-services system. As more people use the social safety net established by state, county and private agencies, the count will grow, officials said.

"It's not stabilizing," said Linda Frazier, director of emergency services for the Red Cross office in Hyattsville, referring to the number of displaced residents needing services.

In Prince George's and Montgomery counties, which have received more than one-third of the arrivals, the Red Cross, churches and county agencies are mobilizing to provide housing in hotel rooms or apartments.

The Maryland State Department of Education reported yesterday that 280 displaced children have enrolled in public schools, most in Montgomery. In Northern Virginia, 134 children have enrolled, officials said.

As of Thursday night, Frazier said that the Red Cross had requests for services from 352 people and that she was expecting to add more to the list by the end of yesterday. Many, she said, had come to Prince George's because of its large black population and strong familial ties to the South.

As she spoke, dozens waited for food stamps, Medicaid assistance and debit cards to buy needed items. County social workers were doing health screenings and providing psychological treatment.

"What we have now is a one-stop shop," Frazier said.

In Montgomery, county officials estimate that 200 storm victims have found temporary shelter.

County Executive Douglas M. Duncan (D) announced that the county was ready to accept up to 1,000 evacuees. There are also plans to place additional arrivals in subsidized rental units, hotel rooms or with families volunteering rooms in their homes.

"If there is a need, we can place them," said David Weaver, a spokesman for Duncan.

Other agencies in the county are working to secure jobs for the victims. Montgomery College plans to waive tuition for students whose schools were in the path of the storm.

Officials in the District of Columbia said they did not have a way of counting the number of evacuees beyond those who arrived in two planes from New Orleans on Tuesday.

After reporting that 295 men, women and children had landed, officials said yesterday that the number staying at the D.C. Armory had dwindled to 178 because some were reunited with friends and family members or those who did not want to remain made other plans.

In Northern Virginia, Loudoun County officials said its Red Cross office has assisted about 140 people. And in Fairfax County, the Red Cross has helped 420, linking them to county and community services and providing cash for food and clothing, said Susan Aarhus, executive director of the Fairfax/Falls Church office.

County and school officials have been meeting with community groups to come up with a plan to help the evacuees settle in should they decide to stay. As in other areas, the county is helping the new arrivals find apartments, and federal vouchers are being made available to help some to pay rent.

Outside the Red Cross office in Hyattsville, County Executive Jack B. Johnson (D) announced that several owners of apartment complexes pledged to provide 100 units for free or at reduced cost.

"We are a county that cares," Johnson said.

Staff writers Maria Glod, Ylan Q. Mui, Tim Craig, Theola S. Labbe and Lori Aratani contributed to this report.

Collette Breaux waits at the Red Cross office in Hyattsville for a debit card. The New Orleans resident is staying with her mother in Hyattsville.Patricia Brooks, in hat, discusses New Orleans with Colleen Wilson. From left are Meredith Dixon, left, Clementine Griffin and volunteer Alphonso Lewis.