We don't know much but Al Michaels just interrupted NBC's Olympics coverage to say that a media bus struck and killed a cyclist in London.

We'll update as we learn more.

UPDATE, 4:53 p.m.: It doesn't look good. Here's the AFP:

An AFP reporter saw a man's legs protruding from under the double decker bus on a slip road outside the Olympic Park and his mangled racing bicycle lay nearby.

A group of around 30 soldiers who had been carrying out security duties at the Olympic Park ran over to the scene, where traffic soon built up causing long tailbacks.

UPDATE, 5:01 p.m.: The AP reports that no one on the bus was injured and there have been no arrests:

Police say the 30-year-old cyclist was pronounced dead Wednesday about 30 minutes after the 7:45 p.m. accident on Ruckholt Road in east London about 1 mile (1.5 kilometers) north of the Olympic Stadium.

Ambulance units including a helicopter-borne unit tried to save the man.