6:56 p.m. Update: The Maryland State Highway Administration says all lanes are now open.

6:10 p.m. Update: The eastbound lanes have partially reopened but expect residual delays.

Original post: An accident on U.S. 50 east just past the exit for Cape St. Claire Road in Anne Arundel County is causing serious delays, according to state transportation data.

All eastbound lanes are closed, with traffic being diverted to Frontage Road. Delays extend for about five miles.

The accident, which includes a reported hazardous materials spill, was reported about 3:30 p.m.