A couple filed a lawsuit Wednesday over the death of their 21-year-old son from acute alcohol poisoning as a result of binge drinking at a university tennis club gathering.

The parents of Akira Takahara filed the suit with the Tokyo District Court against 21 people who attended the gathering, seeking a total of ¥169 million ($1.36 million) in compensation.

Takahara collapsed after downing a liter of shochu distilled spirits with an alcohol content of 25 percent at a meeting of the University of Tokyo, or Todai, tennis club. The students had gathered on July 27, 2012, to secure a viewing spot for a fireworks festival in Tokyo the next day, according to the complaint.

The club members continued drinking after Takahara collapsed and only called an ambulance about two hours later, but he was already dead, the complaint said.

Around 40 members of the club, including some under the legal drinking age of 20, attended the gathering, according to the plaintiffs' lawyer.

Of the sophomores or above accused by the parents, 10 have already agreed to pay ¥2.4 million each. But the other 21 have denied legal responsibility, prompting the parents to file the lawsuit.

"There is no end to drinking incidents resulting in the deaths of students. I hope no parent has to go through the experience of losing a child like this," Toshihiko Takahara, the 52-year-old father, said in tears at a press conference.