Large firework in drainpipe blows out house windows in San Francisco

SAN FRANCISCO - Three windows of a house in the Excelsior district were blown out when a firework "larger than M80" was set off in a drainpipe around 7:40 
p.m., the San Francisco Fire Department said.

The explosion was at a one-story home at 197 Edinburgh St., but there were no injuries, the department said.