Shares of California Pizza Kitchen jumped as much as 20 percent for a time early Wednesday after the New York Post reported a private equity firm was in advanced negotiations to buy the restaurant chain.

The Post reported Wednesday morning that American Securities Capital Partners was working to borrow money to fund the takeover.

However, “the price could not be learned and talks could still fall apart,” the Post said.

The Los Angeles-based California Pizza Kitchen announced its interest in finding a buyer in April, causing its share price to spike to a three-year high above $21. But as weeks passed without news, investors grew cautious and the price slumped to the $13 range.

In early trading on the Nasdaq, the company’s shares hit $20, a gain of more than 9 percent from the previous close of $16.77. By late morning, the price had settled down in the $18.20 range, a gain of nearly 9 percent.