Starbucks executive describes how his life became a nightmare after the company announced its #RaceTogether campaign

A senior Starbucks executive says he was attacked online after the coffee chain began a $4 this week encouraging baristas to talk about race relations with customers.

"I felt personally attacked in a cascade of negativity," Corey duBrowa, the senior vice president of communications at Starbucks, wrote in a post on $4 on Tuesday.

DuBrowa blocked several Twitter users Monday before $4.

"I got overwhelmed by the volume and tenor of the discussion, and I reacted," he wrote. "Most of all, I was concerned about becoming a distraction from the respectful conversation around Race Together that we have been trying to create."

"Race Together" is what Starbucks is calling its new campaign. Critics have attacked the campaign on social media, saying Starbucks is trying to capitalize on racial tensions in the US.

Some of those critics tweeted their concerns directly to duBrowa on Monday. And after he deleted his account, critics accused him of stifling the discussion around race relations that Starbucks' new campaign was said to want to initiate.

In response to his critics, duBrowa said he had since decided to reactivate his Twitter account.

"No matter how ugly the discussion has been since I shut my account down, I'm reaffirming my belief in the power of meaningful, civil, thoughtful, respectful open conversation ?-? on Twitter and everywhere else," he said.

Hundreds of people have responded to his return to Twitter, and the reactions are mixed.