Major Anti-Terror Operation Underway in London

After a brief media blackout, information is beginning to trickle out about this, though much of it is conflicting.  According to witnesses, three men with backpacks were taken away by police and some shots were fired.  We'll continue to update as information becomes clearer.

Update: There has been at least one more raid in another section of town as well.

Update II:  Three of the four 7/21 suspects have apparently been apprehended.

Update III:  Looks like they got the fourth suspect as well today in Rome.