A rare 1939 comic drawing from the adventures of boy hero Tintin sold for 539,880 euros ($673,468) during auctions staged simultaneously in Brussels and Paris on Sunday.
The sketch by Herge was among scores of French and Belgian comic works that fetched a total of 1.89 million euros, organisers said, higher than initial estimates had predicted.
The 1939 India ink and crayon sketch for the cover of the Belgian weekly "Le Petit Vingtième" topped an initial estimate of between 350,000-400,000 euros. It also secured a world record for a Herge cover published in the magazine.
The buyer, who was not identified, made the purchase by telephone to the Millon auction house in the Belgian capital.
Collectors and private investors snapped up a total of 86 out of 101 works that were on sale in the two capitals.
In May, a 1937 two-page spread by Herge depicting Tintin on various adventures with his dog Snowy sold in Paris for 2.65 million euros ($3.58 million), a record for cartoon art in a market where prices have risen tenfold in recent years.