Justin Bieber attending amfAR Gala

Justin Bieber attends amfAR Gala at Hotel Du Cap-Eden-Roc during The 67th annual International Cannes Film Festival in May

FGA /Landov

Bieber poured ice cold buckets of water over his head after being nominated by his manager, Scooter Braun.

Justin Bieber has taken the ALS Ice Bucket Challenge twice now in an effort to help spread the message about Lou Gehrig's disease.

Taylor Swift, Selena Gomez Accept ALS Ice Bucket Challenge: Video

Bieber posted two Instagram videos over the weekend where he’s seen pouring ice cold buckets of water over his head after being nominated by his manager, Scooter Braun. In the first clip on Saturday (Aug. 16), the pop star accepts the challenge while wearing a white tank top and black shorts. After dropping the freezing water over his head, Bieber then nominated Ellen DeGeneres, President Barack Obama and comedian Chris Delia.

The next day, a shirtless Bieber took a second Ice Bucket Challenge and nominated “my Beliebers all over the world” before dousing himself with an even larger bucket of water. “I know you guys got an ice bucket somewhere,” he said.

His plan worked. Shortly after posting the videos, Bieber began retweeting numerous fans who accepted his challenge and also donated money to the cause. “@justinbieber I just donated $20 and I will do the #ALSIceBucketChallenge when my mum buys a bucket haha,” one fan tweeted.

The ALS Ice Bucket Challenge has taken the world by storm, with numerous musical artists and celebrities accepting the challenge and posting videos of the deed. On Aug. 16, Taylor Swift, Selena Gomez, Carrie Underwood, Fifth Harmony and The Vamps were among those who dumped a bucket of ice over their heads. Justin Timberlake, Adam Levine and Lil Wayne have also done their part to help spread the message about Lou Gehrig's disease.