In the aftermath of Saturday night’s crowd surge in Itaewon, citizens joined efforts to save the victims by performing cardio-pulmonary resuscitation and offering other assistance.

Video clips that capture the chaotic scenes shortly after the incident happened show a number of volunteers performing CPR in the street, alongside paramedics and emergency rescuers.

The videos show people calling out for help for medical experts or anyone who knew how to perform CPR.

Lee Beom-suk, one of the doctors who volunteered at the scene, told local TV station YTN that the number of victims increased sharply soon after he joined and soon exceeded the capacity of first responders at the scene.

“I initially saw two victims, but their numbers increased dramatically and emergency medical staff were not enough to help them all. Citizens including other doctors and nurses who were there joined in to help the victims,” Lee said.

But none of the victims he helped was saved, Lee said, adding that they were probably trapped for too long. "Their faces had already turned blue, and their bellies were swelling up."

Lee Gwang-hyung, a 21-year-old who works at a bar near the place where the accident happened, told the local newspaper Hankyoreh that he witnessed the victims receiving CPR.

“Around 11 p.m. when I came out of the store, about 10 people were down on the street and people are taking a turn to perform CPR on them.”

As of 5:30 p.m., authorities said at least 154 people have died in a crush that occurred at a narrow street in Itaewon.

Reports started surging in asking for help from around 10:20 p.m. Saturday night, but it took nearly an hour for rescue workers to reach the site of the incident and were able to help the victims. This could have attributed to the large number of deaths, local media reported.

Medical experts say that a cardiac arrest victim can sustain permanent brain damage after only 4 minutes without oxygen, and death can occur as soon as 4 to 6 minutes later.

In the wake of the accident, South Korea’s TV stations including SBS and MBC have broadcast CPR steps in between commercial advertisements and programs on Sunday.

According to the American Red Cross, to perform CPR, check first if the victim is responsive. If unresponsive, check for responsiveness, breathing, life-threatening bleeding or other life-threatening conditions using shout-tap-shout. Place the person on their back on a firm, flat surface and then push hard and fast (about 5-6 centimeters in depth, 100-120 times per minute) with two hands centered on the chest and shoulders directly over your hands with your elbows locked.

While those who are not trained in CPR are recommended to give hands-only CPR, those who are trained should provide a set of 30 chest compressions and 2 breaths until further support arrives.