A spat between Tesla’s Elon Musk and Greenlight Capital founder David Einhorn intensified on Friday as the hedge-fund luminary fired off a letter via Twitter raising questions about the auto maker’s financial statements.

“The truth is we are much more interested in, and have many questions about, your financial statements,” wrote Einhorn in a Nov. 8 letter.

The missive from Einhorn comes after Musk — swearing he would take a break from the microblogging site — blasted out a response by tweet to a note on blogging site ZeroHedge, which purported to sum up a critical Oct. 30 investor letter from Einhorn.

An Einhorn spokeswoman confirmed the Nov. 8 letter’s authenticity to MarketWatch but wouldn’t comment further. Tesla didn’t respond to an emailed request for comment.

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Addressing Einhorn as “Mr. Unicorn,” — the German translation of that name — Musk responded that the investor had made “numerous false allegations,” without getting specific but he also said that he empathized with Einhorn’s situation.

Tesla’s TSLA, +5.04% stock price has risen since it surprised Wall Street with a quarterly profit last month. Some who have bet that the company’s shares would fall have been unwinding those bearish positions since June as a result, helping partly to drive shares of Tesla further higher.

The electric-car maker’s stock has gained 1.3% year to date, but rebounded 41.5% for the quarter so far. Einhorn’s Greenlight fund declined 4.9% in August, leaving it with a year-to-date return of 15.2%, after a 34% plunge in 2018, which marked its worst year on record, according to Bloomberg.

Musk offered to host a visit by Einhorn to Tesla facilities, saying investors would probably appreciate him “getting smart” on the company.

The Tesla chief also said he would be sending Einhorn “a small gift of short shorts to help you through this difficult time.” Musk apparently sent him a load of shorts in August 2018 too, which he sent images of via Twitter.

Einhorn said he would welcome the opportunity to learn more about Tesla and would take up Musk’s invitation for a visit, adding that previous requests to Tesla’s Investor Relations team had been rebuffed.

“Perhaps, we could spend time together with your CFO, Zach Kirkhorn,” Einhorn wrote, referencing Kirkhorn, who was named chief financial officer of Tesla in March.

He continued to question Tesla’s receivable balances which remain high, adding, “We have dozens of questions like that.”

The letter in its entirety can be viewed here: