Surveillance video shows U.S. Customs and Border officials watching a Tijuana teenager ingest liquid methamphetamine moments before the chemical led to the teen's death.

Cruz Marcelino Velazquez Acevedo, 16, of Tijuana was stopped by federal officials after he entered the U.S. from Mexico through the San Ysidro Port of Entry on November 18, 2013.

NBC 7 has obtained stills from the surveillance video from local attorney Eugene Iredale. He represented the teenager's family.

In his backpack, Velazquez carried two bottles containing an amber-colored liquid -- which turned out to be liquid methamphetamine.

When an agent asked what was in the bottles, Velazquez called the liquid a juice.

At secondary inspection, Velazquez once again explained the bottles contained juice, but agents believed they contained controlled substances.

The family claims in the lawsuit that agents "coerced and intimidated Cruz into taking a big sip from one of the bottles." A previous Medical Examiner report said Velazquez voluntarily took a sip.

Family members argued the teen was "coerced and intimidated" into drinking the liquid and was taken into custody instead of being given medical attention.

"It's true that Cruz was doing something that was against the law. And that he did not have to be doing. That's a fact," said Gene Iredale, a family attorney. "It's also true that they did not point their guns at him or physically threaten him but in a social context in which this occurred, they knew exactly what they were doing."

Around 6:45 p.m. that day, U.S. Customs and Border Protection officials said that 16-year-old Velasquez carried in a bag filled with two amber-colored bottles. He was using his border crossing card.

When agents asked him what was in the bottles, Velasquez claimed they were full of juice. At the secondary inspection area, they told him to take a sip to prove it.

Velasquez hesitates for a moment and then takes a sip. Then another and another. He drank four sips of the concentrated liquid methamphetamine in total.

Three years after his death, the family received $1 million settlement, according to court documents.

After a K-9 alerted agents that Velazquez had controlled substances, agents handcuffed Velazquez and took him into custody.

Shortly after, Velazquez began sweating, and then "screaming in pain and clenching his fists," according to the suit.

In the lawsuit, the family alleged that Velazquez began yelling "the chemicals" in Spanish and then, "Mi corazon! Mi corazon!", or "My heart! My heart!" He began to seize uncontrollably, according to the suit.

Agents called paramedics, who had to sedate the teen before transporting him to Sharp Chula Vista Medical Center.

He was pronounced dead at the hospital several hours later, according to the Medical Examiner. The ME ruled his death an accident.

When asked about the potency of methamphetamine in a liquid form, a member of the UCSD Poison Control center said the substance can show life-threatening side effects within minutes because it hits the stomach quickly.

The agents involved in the case, Valerie Baird and Adrian Perallon, remained with the CBP in San Diego.

Another attorney, Alex Ozols, explained that a Supreme Court case has set a precedent that allows for the use of certain tactics to get a confession, which is an argument the CBP could make.

"What happened here, it looks like their tactic backfired," said Ozols. "They expected this individual to say hey there are drugs in here. I'm not going to drink it. He did start to drink it and that created a problem."

The family attorney said that the agents could have resolved the issue with a simple two-dollar test. He's fighting for the proper treatment of people crossing the border, as well as discipline for bad behavior and better training of agents.