Elon Musk on Friday night explained how he will determine the number of spam and fake accounts on Twitter, hours after he said his bid to acquire the platform was on hold due to the company’s possible underreporting of bots.

Musk, 50, wrote on Twitter that he would calculate the true presence of spam on the platform by analyzing a random sample of 100 followers of popular accounts.

Musk sent shares of Twitter plunging more than 25 percent in pre-market trading as investors surmised he was using fake accounts as a way to back out of the deal.

Stocks of Tesla, which Musk said he could use to fund the Twitter deal, went the opposite route, rising six percent to $770 Friday.