Marathon bomb suspect eludes police, hunt paralyzes Boston

WATERTOWN, Massachusetts (Reuters) - Black Hawk helicopters and heavily armed police descended on a Boston suburb Friday in a massive search for an ethnic Chechen suspected in the Boston Marathon bombings, hours after his brother was killed by police in a late-night shootout.

The normally traffic-clogged streets of Boston were empty as the city went into virtual lockdown after a bloody night of shooting and explosions. Public transport was suspended, air space restricted and famous universities, including Harvard and MIT, closed after police ordered residents to remain at home.