Gunshots shattered the rear window of a Massachusetts Bay Transportation Authority (MBTA) Silver Line bus bound for Dudley Square as it drove near Herald Street in the South End last Friday night, endangering about 40 passengers on board, including an Emerson student. There were no reported injuries, MBTA Spokesperson Lydia Rivera said.

It is not known if the bullets fired were strays or had been directly aimed at the bus. Rivera said the bullets came from outside the bus.

She said the MBTA is interested in eyewitness accounts, as the driver did not notice the damage until he returned to the garage.

Anna Haas, a junior musical theatre major, was heading home when she heard what she thought sounded like gunfire coming from the back of the bus.

“Normally I sit in the back and just listen to my iPod, but for some reason I decided to sit up front,” Haas said.

Then she heard a loud bang, followed by another.

“I didn’t know what happened until I got off and saw the bullet holes in the window,” she said.

Despite Rivera’s belief that the bullets were fired from outside, Haas said she was sure the noises were gunshots coming from inside the bus. Immediately before the shots were fired, Haas said there was a lot of commotion from the rear of the bus.

“I heard someone yell, ‘Don’t close the door! Don’t close the door!'” she said.

Haas said she was frightened for her life during the incident.

“People started screaming and some held their companions closer,” Haas said. “I just acted right away and squeezed through the doors as they were closing [at the next stop].”

Haas said the bus driver seemed unaware of the incident and kept on driving.

Four other people got off with her at the Herald Street stop on the bus bound for Dudley Square. Haas said they didn’t speak English, but also appeared shaken.

“I just ran and crouched down in a corner of a parking lot and started crying,” Haas said.

She then called the Boston Police Department (BPD) and officers arrived on the scene. BPD Spokesman John Boyle said that, although the BPD responded, he could not comment because the crime was under MBTA jurisdiction.

Rivera said the shooting, to the best of her knowledge, was an isolated incident and is currently under investigation.

But, Pam Coppola, a junior print journalism major who also lives in the South End and rides the Silver Line daily, said that the bus she was riding on Tuesday was struck by an object around the Union Park stop.

Coppola, who was not aware of the gunfire on Friday, said she was startled and frightened by the loud noise.

“Something hit the window really hard,” Coppola said. “I’m pretty sure it was someone throwing a rock because the impact on the glass was large, it cracked the window pretty good.”

Other incidents of violence on MBTA transportation include a February 2003 shooting in which a pregnant woman was shot in the stomach on the Orange Line, killing her unborn child. Two men were later indicted for the crime.

In March of this year, a 17-year-old boy was fatally shot in the chest by an 18-year-old companion on an MBTA bus.

Rivera said those who witness dangerous incidents, like Haas and Coppola, should immediately contact the MBTA.

“I urge all customers to report all incidents when they witness something,” Rivera said. “That way they will be easier to investigate.”

Haas said she has ridden the Silver Line since the incident, although the event was a realization of her worst fears.

“It changed my perspective on life,” Haas said. “For a minute I thought I was going to die. Your life literally does flash before your eyes.”

Dan Muse contributed to this report.