Residents were awakened by blasts from the fires on Washington Avenue north of Myrtle Avenue just before 2:15 a.m. Friday.
"I was watching a movie and heard a small boom, so I went to check what was going on," said one resident. "In the backyard I saw lights were flickering but nothing real unusual. Went to the front and noticed that the transformer was on fire."
Firefighters arrived on the scene.
One of the manholes was under a parked Volvo, setting the car on fire.
The situation went to two alarms as crews worked to bring it under control.
ALSO READ: 2 hurt as manhole cover from blast hits elevated subway line
Three apartment buildings on Washington Avenue were left without power.
The cause is unknown, but the hot weather and overnight storms could be a factor.
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