The National Park Service says engineers have found a crack near the top of the Washington Monument presumably caused by a magnitude-5.8 earthquake that shook the East Coast.
Park service spokesman Bill Line said Tuesday night that structural engineers found the crack where the 555-foot landmark narrows considerably.
He says the monument will be closed indefinitely to keep the public safe.
An outside engineering service will study the crack on Wednesday.
The 91,000-ton monument is made of Maryland marble.