A teen is spending his 18th birthday in the Fulton County Jail after he allegedly got up from his seat, rushed toward a man boarding a MARTA bus and fatally shot him.

Jawwaad Nelson was charged with murder in connection with the incident, which occurred about 5:30 p.m. Thursday at the College Park MARTA station.

Witness Jay Stephens said he saw a crowd of people and heard a frightening sound.

"We just heard the gunshots and people started running," he told Channel 2.

The victim, identified as 19-year-old DeAngelo Hill, was taken to Grady Memorial Hospital, where he died.

Channel 2’s Carl Willis was at the scene Thursday night as investigators canvassed a MARTA bus.

In addition to murder, Nelson was arrested on charges of aggravated assault, theft by receiving, possession of a firearm during the commission of a felony and possession of less than an ounce of marijuana, MARTA spokeswoman Alisa Jackson said.

Officials have not released a motive in the shooting.

Hill is the second MARTA passenger killed in the past two weeks. Police believe Charles Richey, 49, of Atlanta, stabbed an unidentified MARTA rider to death Jan. 24.

MARTA released this statement Friday: “In spite of these isolated incidents, MARTA remains one of the safest transit systems in the country. And, in both instances at Avondale and College Park, the suspects were apprehended within 24 hours by MARTA Police.”