Bell's been replying to various Twitter accounts over the last few days -- specifically, those calling him "pedo" and claiming he's a registered sex offender -- and trying to defend himself against the false allegations.

Bell tweeted, "Noooo Immmm Nooooooottttt!!!! You people are going to kill me" in reply to someone who called him a sex offender. He responded to another with ... "Nooooo I wasn't!! You people are destroying my life."

In another back-and-forth, one fan wrote, "Let’s not forget he’s a pedo" ... but another actually defended Bell by saying, "He's not though."

Bell eventually chimed in on that convo with, "Do a second of research This is what I have to live with everyday they are literally going to kill me. Bloods on their hands..."

The examples are endless, and clearly, something that's had a serious effect on the actor/singer ... especially in the wake of going missing last week, and his wife filing for divorce.

As for why the trolls are teeing off on him -- remember, Drake was sentenced to 2 years probation back in 2021 after pleading guilty to one felony charge of attempted endangering children. A woman claimed she and Bell started exchanging sexual messages and photos when she was just 15, and eventually met at one of his shows, where she alleges she performed oral sex on him.

Bell did not have to register as a sex offender as a result of that case ... which is why he's so pissed about the repeated tweets accusing him of that.

TMZ broke the story, Bell was reported missing last Friday, and cops considered him "endangered" before they located him several hours later.

Bell's brother had told cops Drake threatened suicide over child custody issues.

His month got worse when we broke the story his estranged wife, Janet, filed for divorce Thursday.

Interestingly enough, Bell also sounded off about his divorce, tweeting, "I found out my wife filed for divorce from TMZ...check out my new song" and dropping a link to his song "Going Away."