Earthquake in US today!

The earthquake that hit the east coast of the US on Tuesday left minor cracks in the pyramid at the top of the Washington Monument and forced the precautionary closure of Washington DC's schools.

Although no casualties or any serious damage have yet been reported as a result of one of the biggest quakes to hit the east coast, the Washington schools authority issued a statement saying that, while it understood the inconvenience the closure would cause to some parents, it wanted engineers to inspect its 126 school buildings.

The US parks department, which is responsible for many of DC's monuments, reported some minor cracks on the pyramid at the top of the 555ft monument.

The national cathedral in Washington, one of the highest buildings in the city, also suffered minor damage, with several capstones dislodged from its spires.

The quake, which registered 5.8 on the Richter scale, was followed by a tremor on Wednesday morning.

The quake on Tuesday led to the evacuation of the White House, Congress, schools and offices. Many workers then headed home or to the nearest bar to wait for the traffic to ease. Planes were grounded and trains stopped while rails were checked.

The media response to the quake was greeted with mild amusement in California, where tremors are a regular occurrence. Cable channels such as CNN – which, until that point, had been providing almost non-stop reports from Muammar Gaddafi's compound in Tripoli – switched to devote a lot of their coverage to the quake.

The Washington Post led with it on Wednesday, headlining: "Earthquake jolts DC area".

The Post reported that the first warnings of the quake may have come from the National Zoo, where officials said red-ruffed lemurs began "alarm calling" a full 15 minutes before the quake hit and. In the great ape house, Iris the orangutan bellowed 10 seconds before the keepers felt it.

The east coast is bracing itself for the landfall of Hurricane Irene, which is on course to hit North Carolina.