One woman was stabbed in the chest and another struck during a fight aboard a Metrobus early Tuesday in Southeast Washington, according to a Metro spokeswoman.

The altercation occurred about 2:15 a.m. in the 2200 bloc of Martin Luther King Jr. Boulevard in Anacostia, on a bus making its way to Congress Heights.

Caroline Lukas, a Metro spokeswoman, said an adult female passenger alerted the bus driver that she had been stabbed. The driver pulled over and called police.

Lukas said the woman suffered non-life threatening injuries, and another woman was struck in the head with some sort of object. She said the attacker escaped and was being sought with the help of video surveillance inside the bus.

Lukas said police are trying to learn whether the attacker and the victims knew each other. She did not know what they were arguing over. The victims were being treated at a local hospital.

The spokeswoman said she did not know how many passengers were on the bus at the time. The stabbing comes after a series of crimes involving Metro last year, including a fatal stabbing at the Woodley Park Metro station, a fatal shooting of a woman as she boarded a bus holding her child and rocks being thrown at busses in Southeast.