The Philadelphia 76ers president of basketball operations, Bryan Colangelo, has become involved in a bizarre story involving fake Twitter accounts and the size of his collar.

According to The Ringer, a number of Twitter accounts could be linked to Colangelo as they followed his son and some of his son’s basketball team-mates. The Ringer also contacted the 76ers to see what would happen if it told the team about two of the five suspicious accounts. Later that day, the three accounts the Ringer hadn’t mentioned to the Sixers were switched from public to private.

Some of the tweets attacked Colangelo’s own players. Particularly damaging could be ones that criticized Joel Embiid, one of the young stars the Sixers hope to build their team around. “Too bad that Embiid danced like a fool and the whole disaster happened, next time he will think twice before mocking his team,” said one tweet after Embiid had gone to a Meek Mill concert. Another asked “Why didn’t you tell docs knees hurt before Houston?”

The 76ers said on Wednesday they were investigating the claims. “The allegations are serious and we have commenced an independent investigation into the matter,” the team said in a statement. “We will report the results of that investigation as soon as it is concluded.”

Colangelo has admitted he used one of the accounts but denied using the others. “Like many of my colleagues in sports, I have used social media as a means to keep up with the news,” he said in a statement. “While I have never posted anything whatsoever on social media, I have used the @Phila1234567 Twitter account referenced in this story to monitor our industry and other current events. This storyline is disturbing to me on many levels, as I am not familiar with any of the other accounts that have been brought to my attention, nor do I know who is behind them or what their motives may be in using them.”

While some of the tweets are damaging to Colangelo professionally, others are more innocent if a little embarrassing. Much time was spent defending the size of Colangelo’s collars. “That is a normal collar. Move on, find a new slant,” said @Enoughunkownso1, one of the accounts linked to Colangelo after another user had questioned his dress sense.

On Tuesday, Embiid said Colangelo had spoken to him about the story and denied he was behind the tweets. “I talked to him and he said that he didn’t say that,” Embiid said. “He called me just to deny the story. Gotta believe him until proven otherwise. If true, though, that would be really bad.”

Colangelo has been with the Sixers since 2016. The team made the playoffs this season around a core of talented young players, and are expected to be one of the dominant teams in the NBA Eastern Conference in the years to come.