Paintings by Van Gogh Stolen in Amsterdam

AMSTERDAM, Netherlands -- Less than a week after millions of dollars' worth of gems disappeared during a diamond exhibition, thieves broke into another major Dutch museum on Saturday and made off with two works by Van Gogh.

It is the second time the Van Gogh Museum has been burglarized, all the more surprising since security was stepped up after the first break-in 10 years ago. The museum in Amsterdam boasts the world's largest Van Gogh collection, more than 200 paintings and hundreds of drawings.

"This is the worst thing that can happen to any museum," said the director, John Leighton.

The alarms went off about 8 a.m., about two hours before the museum opens. By the time police got to the scene, the thieves had vanished, Leighton said.

Police had responded quickly and hoped to find the thieves still in the building. Instead they found a 5-meter ladder leaning against the rear of the building, as well as a rope. Apparently the thieves climbed up to the second floor and broke in through a window, police spokeswoman Elly Florax said.

Leo Schenk, of the Dutch Museum Association, said security in the Netherlands was among the world's best. "A lot has been invested in electronic security, but you can't rule out the human factor," he said. It was unclear whether the burglars had inside help, he said.

Leighton said two oil paintings are missing, both from early in Van Gogh's career. They "have no market value since they were not for sale, but comparable paintings sold for several million dollars," he said.

One is the "View of the Sea at Scheveningen," a small picture of a boat setting off into a stormy sea.

Painted over two days in 1882, the thick paint contains grains of sand blown onto the canvas from the beach where the artist worked. It is one of his first major pieces.

The other is "Congregation Leaving the Reformed Church in Nuenen," from 1884-85, a picture of the village church where Van Gogh's father had been a pastor.

"The 'Reform Church' was emotionally important. He probably meant it as a souvenir for his mother," Leighton said.

Both were too well known to sell on the open market, but Schenk said they may be offered for ransom. "In many cases, paintings were recovered. Sometimes it takes an eternity," he said.

Police turned away the public Saturday while investigators combed the building for clues and curators rearranged the paintings to cover the blank spaces on the walls.

In 1991, thieves made off with several priceless Van Goghs, including one of the famous "Sunflowers" paintings. All were quickly recovered.

Leighton refused to discuss security, including what measures were taken after the first break-in.

It was the second high-profile heist in the Netherlands in a week. Last Monday, thieves raided a diamond exhibition at the Museon in The Hague, about 50 kilometers south of Amsterdam. Museum officials said millions of dollars' worth of gems were taken.