NEW YORK (CBSNewYork) — CBS2 has learned of another attack on a Metropolitan Transportation Authority bus.

The NYPD responded to an area along New Lots and Vermont avenues in Brooklyn on Thursday afternoon after a suspect threw a rock in to the window of a B15 line bus.

Neither the driver nor passengers were injured in the attack, Transport Workers Union Local 100 officials said.

Police said the incident happened at around 12:30 p.m.

The suspect is described as a black man in his 20s wearing a multi-colored shirt and khaki pants. Police said he fled west on New Lots Avenue.

The attack was the fourth on an MTA bus in the last week, though police did not immediately say that Thursday’s incident is related to the other three.

MOREMTA Bus Drivers Express Concern Following Recent Violent Incidents Along B15 Route To JFK Airport

Investigators told CBS2’s Reena Roy the first two incidents on the B15 line happened within hours of each other last Thursday, with a passenger spraying an unknown substance on each driver and running off.

Then on Monday, the TWU said a B15 was stopped when a man approached the bus. The driver opened and then quickly shut the window when the suspect flashed an aerosol can and then banged on the glass before smashing it.

All three drivers were taken to local hospitals, treated and released.

Police released an image of a suspect in all three prior attacks.

Please stay with CBS2 and CBSNewYork.com for more on this developing story.