Transformer explosion rocks midtown Manhattan

NEW YORK (Reuters) - A transformer exploded in midtown Manhattan on Wednesday, creating a roar and a huge plume of smoke and sending pedestrians fleeing from the area in scenes reminiscent of the September 11 attacks.

Police at the scene said 15 to 20 people had been taken to the hospital. CNN said three of the injured had been admitted to the New York Presbyterian Hospital emergency room.

In Washington, a U.S. Department of Homeland Security official said there was no apparent link to terrorism.

"Right now it is a localized incident," said the official, speaking on condition of anonymity. "At this point, we see no nexus to terrorism."

Officials said a ruptured steam pipe appeared to have caused the transformer to blow.

"This is not a terrorist-related incident. It's a steam explosion," said Deputy New York Police Department Commissioner Paul Browne.

The explosion erupted during the evening rush hour in one of the busiest sections of New York City, near the transportation hub of Grand Central station.

A loud constant roar rang out through the streets.

"We have a building that's a bit shaky, but nothing has collapsed," a police spokeswoman said, contradicting a witness report from the scene that a building had collapsed.

Pedestrians sprinted from the scene, many with cell phones glued to their ears, some crying. Some were covered in white ash and soot.

"It looked like the World Trade Center had exploded. I saw rocks and pebbles coming down. As I was running I got pelted in the head by rocks and concrete. Steam came up and then the ground started breaking up," said Reggie Evans, an office administrator who was covered in mud.

Another man said he was drinking in an Irish pub near Grand Central station when security guards rushed in and told everyone to evacuate and head west.

"There is debris falling, get back," a fireman told onlookers. People were being kept a block away.