An explosion in a manhole on Morrissey Boulevard in Dorchester on Wednesday night knocked out power to the Boston Globe for nearly three hours.

The blackout occurred at 9:45 p.m., cutting power to the entire Globe building including the newsroom and pressroom, after one of the two electrical cables that feed into the building stopped working as a result of the explosion, according to the company’s production manager, Larry Coan.

Coan worked with NSTAR into the night to try to restore power as employees managed to get out the first edition of the newspaper and a limited later edition. The start of the Globe’s presses was delayed by the outage, and some readers may receive their papers late.

The bostonglobe.com and boston.com websites continued publishing through the blackout with the use of backup power.

A NSTAR representative said the cause of the explosion and resulting fire was under investigation. Power was restored just after 12:30 a.m. on Thursday.

The Globe was the only building on the road affected, Coan said.