Democratic House members representing the Washington region urged stricter White House social distancing measures and cooperation with local public health officials Tuesday as the nation’s capital notched its highest daily coronavirus caseload since the summer.

D.C. reported 105 new confirmed cases, the highest in a single day since June 3, when caseloads were falling near the height of the pandemic. City officials said they are monitoring the rise but cautioned that it’s unclear whether the spike is tied to a growing outbreak at the White House.

A Rose Garden event on Sept. 26 suspected of being at the center of the outbreak came as D.C. was recording its lowest number of average daily infections since early July, with a rate lower than that of most states. The rolling seven-day average of new cases this month has hovered below 40 after trending downward for weeks.

City health officials said they will look for trends in new infections but warned against drawing conclusions after a one-day increase in cases.

D.C. leaders noted that only city residents are reflected in the city’s coronavirus tally and that many federal government officials do not declare D.C. residency. Not all testing on federal officials is reported to the city government.

The rise also could be attributed to a backlog of more than 8,000 test results the city recently received on a single day.

The growing spotlight on the White House outbreak appears to have led to a rise in residents seeking coronavirus tests this week. D.C. performed 3,964 free tests at its public sites Monday, an 83 percent increase over the 2,161 tests performed a week earlier.

The potential for the virus to spread across the capital region prompted Democratic House members representing D.C., Maryland and Virginia on Tuesday to condemn the Trump administration’s handling of the outbreak, urging stricter public health protocols at the White House.

“We are alarmed and dismayed by the casual disregard for the health of our community, including constituents who work at the White House as staff, agents or officers of the United States Secret Service, journalists of the White House Correspondents’ Association, and the general public,” they said in a joint statement.

The statement was signed by D.C. Del. Eleanor Holmes Norton; Majority Leader Steny H. Hoyer and Reps. Anthony G. Brown, John Sarbanes, Jamie B. Raskin and David Trone of Maryland; and Reps. Jennifer Wexton, Gerald E. Connolly and Don Beyer of Virginia.

They urged the Trump administration to disclose the number of infected White House personnel, expedite contact tracing of people exposed to the president and others, and mandate face coverings and social distancing on White House grounds. The lawmakers objected to President Trump’s playing down of the virus.

“The American people will never trust the Administration to keep them safe if the White House cannot protect its own staff,” the lawmakers wrote.

Norton, D.C.’s nonvoting representative to Congress, separately wrote a letter to White House physician Sean Conley asking why his office has declined the city government’s offer to help conduct contact tracing. She also asked whether anyone in the Trump administration had directed him to rebuff the city’s efforts to help.

“Many White House staffers live in the District, and it is imperative that their D.C. neighbors are aware of the risks associated with this ongoing outbreak at the White House,” Norton wrote.

Local leaders in the Washington region continued to voice concerns that the White House outbreak could reach their jurisdictions.

Fairfax County Board of Supervisors Chairman Jeff C. McKay (D-At Large) said Tuesday that county health officials haven’t been notified of confirmed cases with ties to the outbreak. He criticized the White House’s lack of transparency in recent days, which he said is putting lives at risk in Virginia’s most populous locality.

“I am concerned about how the White House’s COVID outbreak could impact our residents, many of whom are administration employees,” McKay said in a statement. “Also, our community has responded to the need to protect one another by social distancing, masking, and following health guidelines and we should be able to expect the same care from the President.”

In Maryland, Anne Arundel County Health Officer Nilesh Kalyanaraman said he was looking into whether the jurisdiction would release information if a county resident contracted the virus during the Rose Garden event.

The greater Washington region on Tuesday recorded 1,143 new infections and 21 virus-related fatalities. Virginia had 625 new ­cases and 15 deaths, and Maryland had 413 new cases and six deaths, in addition to D.C.’s 105 new cases and zero deaths.

The seven-day rolling average of new coronavirus infections across Virginia, Maryland and D.C. has ticked slightly upward in recent days, standing at 1,416 ­cases Tuesday — up from about 1,300 one week ago.

While Virginia’s average daily caseload has held steady over the past week, state health officials painted a rosier picture in Northern Virginia. State Health Department data shows the region has the lowest rate of virus transmission in the state.

Each week, the department notes the coronavirus’s community spread in six regions of the state. Its latest numbers indicate Washington’s Virginia suburbs have a low transmission rate — and trending downward — while most of the state is at a moderate community transmission level.

The seven-day average of new cases in Northern Virginia stood at 163 on Tuesday, with October’s daily caseloads in the region falling to their lowest levels since July.

In D.C. on Tuesday, city leaders took steps to help residents struggling financially during the pandemic, passing several bills meant to help tenants. The D.C. Council approved emergency legislation to bar landlords from posting eviction notices while a moratorium is in place through the end of the year.

Although tenants cannot be forced out for failing to pay rent during the pandemic, some activists have reported instances in which landlords are initiating cases to pressure tenants to pay. The bill goes to Mayor Muriel E. Bowser (D) and would take effect immediately if she signs it.

The council also sent the mayor bills to ease eligibility criteria for rental assistance and to tighten eviction protections for tenants, including prohibiting evictions when unpaid bills are lower than $600 and authorizing city courts to seal eviction cases from a person’s record, among other provisions.

Council members Charles Allen (D-Ward 6) and Mary M. Cheh (D-Ward 3) also successfully introduced an amendment to the eviction legislation to require that landlords provide photographic evidence that they served tenants with eviction notices. The language was a response to an investigation published by DCist and Spotlight D.C., which found hundreds of discrepancies in eviction cases that suggested tenants often weren’t notified of cases against them.

D.C. is also the latest jurisdiction in the region to offer guidelines for Halloween and Día de los Muertos activities. City health experts on Tuesday advised that trick-or-treating, haunted houses or joining large crowds are considered “high-risk” activities and should be avoided.

Officials suggested that residents hold virtual events or decorate their homes instead of hosting gatherings. Those who do meet with others in-person should maintain social distancing and wear face coverings, even with Halloween costumes, according to city guidelines.

Ovetta Wiggins and Antonio Olivo contributed to this report.