U.S. Raises Threat Level for Mass Transit - New York Times: "Government and transit officials in the United States were intensifying security today, especially around mass transit systems, in response to the series of deadly explosions during the morning rush in London.

Homeland Security Secretary Michael Chertoff said at a midday news conference in Washington that the terror alert level for mass transit systems was being raised to orange, the second-highest level on the five-level scale."

(Via NY Times.)