A major water-main break under Harrison Avenue at Perry Street shortly after 9:15 p.m. has buckled the street, swallowed cars, created water problems as far away as G Street in South Boston and forced Eversource to turn off the power in nearby buildings.

BosGuy watched Boston fire crews as they arrived at the scene of a problem with a 30-inch BWSC main at the intersection:

Police cited one driver for collapsing a weakened sidewalk in an attempt to move his car out of the floodwaters.

More flooded cars (photo by BFD):

Meanwhile, reports are flooding in of the sudden end of water service in the Thomas Park/G Street area of South Boston.

One resident in that area noticed water slowing to a trickle - not something he wanted to see in the middle of a stay-at-home advisory with a baby who drinks formula that requires water:

Boston Water and Sewer told me the problem was at Thomas Park and hung up. I took a walk around there and saw no-one, no crew, and no break... clearly a lie. Called 911 they said no water is not an emergency, transferred me to the police who referred me to 311... they couldn't even tell me if the water was safe or if I should go buy bottled water. I understand the city is a mess right now... but if we are stuck at home and can't rely on water we need to know and go buy some.

One South End resident, living in a suddenly blackened building, went outside to take a look:

Residents in Roxbury and even Jamaica Plain reported yellow water. One Seaport resident reported "a trickle of gross water" from her tap.

As Eversource turned off power to nearby buildings, some residents found their fob-based electronic locks no longer worked.

At 11:13 p.m., BWSC reported: