Sharina Byrd describes her ordeal.

It was near the end of another routine run for an MBTA driver just settling into her route. But then, out of nowhere, a large man grabbed Sharina Byrd's neck with one hand and took control of the 86 bus's steering wheel with the other.

Byrd, a Dorchester resident who has only been driving an MBTA bus without an instructor for three weeks, instinctively pulled the emergency brake up with her left hand, stopping the bus and keeping it from careening into traffic and parked cars on the other side of Chestnut Hill Avenue in Brighton Thursday night.

At a press conference at the Sullivan Square T stop - where her route begins - Byrd described what happened as she approached the final stop on a run at Cleveland Circle around 7:30 p.m. Everything was routine. There were about 15 passengers onboard. And then, "this guy just came out of the blue and grabbed my neck," she said. "I thought I was being hijacked."

As the man, identified as Donald Lyons, 52, of Everett, kept his grip on her - strong enough to hold her, but not to choke her - he reached over with his other hand and turned the wheel to the left, sending the bus onto the other side of the road. As she pulled up the brake - by her left side - she began yelling "Tell me what you want, just tell me what you want!" She said Lyons mumbled something incomprehensible. As soon as the bus stopped, she opened the door. At first, he seemed ready to attack her, but he stumbled out and fled, she said.

Byrd said she doesn't remember Lyons even getting on the bus. None of the passengers rose to stop him, but Byrd said they probably didn't even know what was going on - her typical passengers tend to be college students with their noses in a book or phone. A woman sitting near the front did ride around with an MBTA police officer afterwards - and then raced back to the scene to report the man with trouble keeping his pants up on Comm. Ave.

Byrd credited the training she got at the T for helping her remain calm and doing what she needed to do to keep her passengers and herself safe. Byrd has actually been driving a T bus for 2 1/2 months now - but until three weeks ago, she had an instructor with her.

The Suffolk County District Attorney's office reports Lyons was ordered held in lieu of $10,000 bail at his arraignment Wednesday in Brighton District Court.