Batman made his first appearance in Detective Comics No. 27. This copy of the 1939 comic sold at auction in New York on Thursday for $1.075 US. (Heritage Auction Galleries/ Associated Press)

A rare 1939 copy of the first Batman comic sold for $1.075 million US at auction in New York on Thursday, narrowly beating the $1-million US selling price of the first Superman comic three days earlier.

The copy of Detective Comics No. 27, which shows Batman swooping down on a villain, commanded the biggest price on record for a comic book, said Barry Sandoval, Dallas, Tex.-based director of operations for the comic book division of Heritage Auction Galleries.

Both the bidder and the seller remained anonymous. Sandoval said the consignor bought the comic 40 years ago for $100 US.

"It pretty much blew away all our expectations," he told the BBC. "We can really say that Batman has nosed out Superman, at least for now."

On Monday, a copy of the 1938 edition of Action Comics No. 1, the first Superman comic that came out a year earlier, was sold on the auction site ComicConnect.com for $1 million US to a private buyer. It shows Superman lifting up a car.

Both comic books were in excellent condition.

Shirrel Rhoades, former publisher and executive vice-president of Marvel Comics, told ABC News that the two sales will probably keep prices buoyant.

He said the Superman comic is perhaps more historic than the Batman book. When they were issued in the 1930s, both comics sold for 10 cents US.

"We're probably seeing a bit of a feeding frenzy," Rhodes said.

(With files from The Associated Press)