Interpol joins search for stolen Van Gogh paintings

A review of security at one of the world's most tightly guarded art museums, dedicated to Vincent van Gogh, was under way yesterday after burglars stole two of his paintings with the help of a ladder, a rope and something to break a reinforced window.

Interpol is helping in the search for the two early Van Gogh works. It is thought that those responsible may now attempt to dispose of them on the black market, use them as security for drugs deals or offer their return for a ransom.

Police and the Van Gogh Museum in Amsterdam said yesterday that they had no leads as to the whereabouts of the stolen paintings or the people who took them.

The thieves were apparently easily able to break through reinforced glass and make off with paintings worth millions of euros after climbing on to the roof of the museum, where 800 works by the Dutch artist are kept, early on Saturday.

Several Van Goghs stolen from the same museum 10 years ago in a heist likened to events in The Thomas Crown Affair were discovered later in a car and returned.

This time, the burglars scrambled on to the roof shortly before 8am using a 15ft ladder leaning against the rear of the building opposite Museum Plein park. From there, they jumped on to another section of the building, smashing through a reinforced glass window leading to the first-floor room, devoted to Van Gogh's early portraits and landscapes. The gang then made its escape by shinning down a rope to the street below.

A woman living close to the museum told police she had been woken by the sound of breaking glass. When she looked out of her bedroom window she saw "a man standing on the roof of the famous Van Gogh museum across the road with a painting under his arm", Dutch television said.

Remco Gerritsen, a spokesman for Amsterdam police, said there were several witnesses. The alarm went off the moment the window was broken and two security guards on duty called the police. "Within minutes, we were at the scene but it was unfortunately too late. The robbers had already made their getaway," he said. "They obviously used a heavy hammer or axe to break the window, made of reinforced glass. Now the museum will be seriously reviewing that part of its security arrangements."

The stolen Van Goghs are described as significant but "not top" exhibits in the museum. One of the stolen paintings is View of the sea at Scheveningen, a beach scene painted in 1882, which has grains of sand, blown up from the beach as the artist worked, embedded in the thick paint. The second is an 1884-85 painting of the congregation leaving church at Neunen in Brabant, where van Gogh's father had been pastor.

Long queues of visitors were readmitted to the museum two hours before closing on Saturday and yesterday, it was business as usual. The blank spaces had been replaced by works in the same genre – Two Women on the Moor and Woman lifting Potatoes.

The art raid came less than a week after jewel thieves made off with diamonds worth more than €5m (£3m) from another Dutch museum. Police investigating the theft of the Van Gogh masterpieces do not believe that the two robberies are connected.