WASHINGTON — The House side of the U.S. Capitol, which closed temporarily Thursday, has reopened.

The Architect of the Capitol released this statement at 9:20 a.m. about the reopening:

“The House Side of the Capitol has reopened to Members and Staff with certain areas remaining closed, specifically the East Grand Staircase from floors 1 to 3 and room H-324. All other areas of the House Side of the Capitol will return to normal operations, including tours of the Capitol Building.”

At 8:20 a.m., the office explained why the House side was closed.

“During ongoing asbestos abatement work there was a potential release affecting the House side of the Capitol. Samples have been collected to determine whether there was potential exposure. AOC and USCP are investigating and will provide updates when available.”

The U.S. Capitol Police hazardous materials team has been on the scene since about 2:30 a.m. to 3 a.m., Capitol Police say.

The Architect of the Capitol, which handles maintenance of the building, conducted tests before reopening the area.

As the incident began the House Door and South Door were temporarily closed, but the south barricade was open, Capitol Police said. Tours of the Capitol building were temporarily suspended. Tours of the visitor center were not affected.

WTOP’s Kristi King, who is on the scene, reports staff and congressional members have been let back into the building.

House Republican leaders say they are delaying the start of business due to an accident involving asbestos.

In a statement, House Speaker John Boehner, R-Ohio, said the House would not convene at 10 a.m. EDT for morning business, but lawmakers were expected to convene at noon to begin legislative work.

The Associated Press contributed to this report. Follow @WTOP on Twitter and on WTOP Facebook page.