(CNN) -- Police have recovered two of the four Impressionist paintings stolen earlier this month in a daring museum heist, police in Zurich, Switzerland said Tuesday.
Claude Monet's "Poppies near Vetheuil" has been recovered by Swiss police.
The Monet and van Gogh oil paintings were in good condition, police said, and the search continued for the other two -- a Cezanne and a Degas.
A parking lot attendant at the Psychiatric University Hospital in Zurich found the paintings Monday afternoon in the back of an unlocked white car, police said.
It was not clear how long the car, an Opel Omega with stolen license plates, had been parked on the lot, police said.
"The two paintings, worth about 70 million francs($64 million), are in good condition and are still protected by the original glass covering," police said in a statement.
Three masked men stole the four paintings in what police called a "spectacular" heist Feb. 11 at the E.G. Buhrle Collection -- among the finest collections of Impressionist and post-Impressionist art in the world.
One of the men threatened personnel at the museum's front door with a pistol and forced them to the ground, police said, while the other two men went into an exhibition room and stole four oil paintings by Paul Cezanne, Edgar Degas, Claude Monet and Vincent van Gogh.
Afterward, the three men loaded the paintings into a white car parked in front of the museum and then drove off, police said.
The paintings recovered Monday are Monet's "Poppies near Vetheuil" and van Gogh's "Blossoming Chestnut Branches." Still missing are Degas' "Count Lepic and his Daughters" and Cezanne's "Boy in a Red Vest."
The four paintings are worth a total of about $163 million (180 million Swiss francs).
A reward of $91,000 (100,00 Swiss francs) has been posted for information leading to the return of the paintings, police said.
A Zurich police task force, which includes an art expert, had received tips from around the world, police said. The task force was looking into possible connections with other art thefts inside Switzerland and abroad.
The Zurich heist followed the recent theft in Switzerland of two paintings by Pablo Picasso, said Bjoern Quellenberg, a spokesman for the Kunsthaus, another major art museum in Zurich.
The director of the Kunsthaus serves on the E.G. Buhrle private art foundation's council, Quellenberg said.
In that theft, thieves stole the 1962 "Tete de Cheval" ("Horse's Head") and the 1944 "Verre et Pichet" ("Glass and Pitcher") by Picasso. They were on loan from a German museum and valued at $4.5 million when they were stolen February 6, according to news reports. E-mail to a friend