Zayn Malik was noticeably absent when One Direction appeared on the "Today" show.

Host Matt Lauer was not convinced that Malik had missed the performance because he was sick, notes Us Weekly.

"There's obviously a lot of concern, a lot of fans have been tweeting overnight," Lauer said. "There's been a lot of action on social media about him. Is it something more serious than just a minor illness? There have been rumors of substance abuse. What's going on?"

Liam Payne defended Malik and said that he was just sick at home.

Since the show, Malik called out Lauer.

"I'm really angry and upset by what was said on the 'Today' show," he said according to JustJared. "I was really ill at the weekend, that's why I couldn't fly to America."

Malik added that he was disappointed that he missed the release of the album, but that as soon as he is in good health again, he will join the rest of One Direction in promoting "Four."

One Direction fans were also angered, and took to Twitter to slam Lauer.

One said, "My mom even wants Zayn to sue Matt Lauer for slander. He's a jerk."

Another said, "Dear media, Go drink some acid. Acid will help you to think before you spread rumors about Zayn when he's/was SICK."

Some other fans were a little more positive and said that Malik would probably be back with the group by Thursday.

In other One Direction news, the band has recorded a song for "Sesame Street," DailyMails By changing the words to its hit song, "What Makes You Beautiful," One Direction taught children about the letter U.

"Twenty-six letters are in the alphabet, but we're here to sing about U," said the band for its new song.

Watch the video of 1D's "Sesame Street" appearance below.