Eversource reports nearly 1,900 homes and businesses in a swath of Roxbury along Melnea Cass Boulevard - and into South Boston - are without power. Among the affected buildings: 1010 Massachusetts Ave., home to the Boston Public Health Commission, ISD and the Zoning Board of Appeal, which has turned to battery-powered laptops to try to continue its scheduled hearings for today.

Eversource says it hopes to begin restoring power around 3:30 p.m., with the final outage eliminated by 5.

Update: Restoration time pushed back to 2:15 a.m.

The Boston Fire Department responded to 265 Main St., near School Street, in Charlestown when a manhole exploded around 5:45 p.m. As of 9:20 p.m., Eversource is reporting 295 homes and businesses are without power, which it hopes to restore by 10:15 p.m.

The state Energy Facilities Siting Board recently approved plans by Eversource to build a large new underground substation in Kendall Square and 8.5 miles of new high-voltage lines connecting it to other Eversource substations in Brighton and Somerville to deal with growing demand from new construction and electric vehicles - and Vicinity Energy's plans to convert its Kendall Square steam-generating boilers to electric power. Read more.

A Hyde Park homeowner and a Cambridge resident last week filed what they hope will be a class-action suit against Eversource for what they charge is constant false advertising and marketing about the supposed environmental and health benefits of natural gas, claims they say are belied by recent scientific studies and even the company's own statements, even if buried away in footnotes in documents most people will never read. Read more.

Eversource reports some 890 residences and businesses in Hyde Square lost power around 11:15 p.m, Wednesday, and are not expected to get it back until 5 a.m.

It's the first major blackout in JP since Jan. 18.

Update, 10:50 a.m. Eversource says it's restored almost all the power, except to 10 customers.

Around 9 p.m., the lights began blinking out in Jamaica Plain. As of 9:35, Eversource is reporting 4,438 homes and businesses in Boston without power, most of them in JP, and most of those clustered in the area between Jamaica Pond, the Arboretum and Franklin Park, about as far north as Parley Avenue and Green Street. Read more.

Update 11 p.m.: The number of businesses and homes without power is up to 7,959.

Eversource reports a series of power outages from just north of Franklin Park up to Boston Medical Center and areas near Tremont and Dartmouth street to the turnpike. Some 204 business and homes were blacked out as of 10:05 p.m. - as well as traffic and street lights.

Update, 12:45 p.m.: Outage numbers now around 6,112 in Boston, with numerous outages in Hyde Park and Mattapan.

As of 9:30 a.m., Eversource reported more than 3,400 businesses and homes in Boston have lost power - including 1,600 or so in Roxbury, where falling tree limbs knocked out power at 6:32 a.m. and 1,400 in Jamaica Plain, where the power went off at 8:09 a.m.

Update, 3:15 p.m. Eversource reports 139 homes and businesses still without power in Boston, but no outages in Dedham, Brookline and Newton.

Eversource is blaming "equipment damage" for widespread outages that started around 10:45 a.m. in an area that extends from Brookline and Newton streets in the north to most of West Roxbury and Dedham in the south. Parts of Roslindale as far east as Roslindale Square are also affected. Read more.