LIVE UPDATES: At least 149 killed in Halloween derailment

At least 146 people were killed and 150 injured in the attack Visible crowd increase During the crowded Halloween celebrations in Seoul Saturday night, according to the head of the Yongsan Fire Department.

Here are the latest developments.

The death toll may rise: With local hospitals treating dozens of injured from the Halloween emergency in Seoul, the death toll likely to increaseA local health official said. Choi Jae-won, head of the Yongsan Health Center, added that the cause of injuries and deaths in the accident had not been officially confirmed.

The official blames the crowds: A local fire official described the emergency as a “supposed stampede,” but the investigation is just beginning. Few details were provided on specific injuries. Yonhap News Agency mentioned Dozens of people went into “cardiac arrest” and had difficulty breathing.

The authorities said The emergency was not due to a gas leak or a fire in the popular nightclub district. They began receiving reports of people being “buried” among the crowds there around 10:24 p.m. local time (9:24 a.m. ET) on Saturday.

Witnesses noticed a chaotic sceneAn eyewitness said: People was crammed On a narrow street, she couldn’t breathe. “I saw people turning to the left side and I saw the person approaching from the other side,” Song Sehyun told CNN. “The person in the middle was jammed, so they had no way of communicating. They couldn’t breathe.”

This was reported by CNN’s Will Ripley Long line of stretchers The formation on the street will be used to take the bodies from the scene.