Thieves removed two Picasso paintings valued at €50 million (£33.7million) from a flat in one of the most heavily guarded districts of Paris as the owner, a granddaughter of the artist, slept. There was no trace of forced entry.

Police said last night that they were working on a number of theories about the theft of a celebrated 1931 portrait of Picasso’s daughter, Maya with Doll, and a 1961 portrait of his second wife, Jacqueline. They were taken, with a drawing, at about 4am from the flat of Diana Widmaier-Picasso.

Ms Widmaier-Picasso, 34, and a male companion were woken by noises in the small hours but went back to sleep in the first-floor flat of a mansion on the Rue de Grenelle in the 7th arrondissement. They found the art missing in the morning. The thieves had taken Maya with Doll from a wall in its frame, and the Jacqueline portrait was removed from its frame with a knife.

The robbery was the biggest involving the often-stolen master’s works since 11 Picassos were taken from the Riviera villa of Marina Picasso, another grandchild, in 1989. They were recovered quickly.

The district where yesterday’s theft took place is one of the most exclusive, home to the Matignon mansion, residence of the Prime Minister, as well as the National Assembly and most government ministries.

The paintings were among several Picassos in the apartment, which was well protected by security arrangements, said Paul Lombard, the Picasso family lawyer.

“The family is shocked by this theft,” he said. “They were especially attached to Maya with Doll. It was of huge sentimental value to them.”

Completed in 1938, it is one of Picasso’s classic oil paintings done in bright shades of green, blue and red and depicting young Maya in pigtails cradling a doll dressed in a sailor suit.

Maya was the mother of Ms Widmaier-Picasso. Her mother, in turn, was Marie-Therese Walter, who was Picasso’s companion during the late 20s and 30s. He then married Olga Khokhlova.

The stolen portrait of Jacqueline Roque was painted the year that the couple were married, and rates among the most beautiful of scores of portraits of Picasso’s second wife, Mr Lombard said.

Detectives said they had three theories. The theft might have been commissioned by an art lover who sought the paintings for a secret collection. They might have been stolen for later insurance “ransom”. A third possibility was that thieves came across them by chance during a burglary.

Ms Widmaier-Picasso, an art historian, published a book on the erotic art of her grandfather in late 2005. She said that she had never met her grandfather, who died in 1973 when she was one, but her eyes had been opened to his art when her mother took her to an exhibition when she was 15. “I discovered sexuality thanks to my grandfather,” she told le Parisien.

The Catalonian artist, who lived in France most of his life, left 10,000 paintings, drawings, sculptures and other works that were valued at the time at £125 million.

Rogues’ gallery

1976: In one of the biggest robberies in France, 118 Picassos were stolen from a museum in Avignon. All were recovered

1994: Seven works from Picasso’s blue and rose periods, valued then at £66 million, were stolen from a Zurich art gallery

1997: A gunman ripped Tete de Femme from a London art gallery wall and fled in a taxi but the work was later recovered

2004: Still life was stolen from the Pompidou museum in Paris only to be found three months later

Maya with doll

Picasso’s many hundred portraits of children were important to the artist who sought to see the world as if he were a child. But where his early blue and pink period images had a sentimental melancholy, this portrait of Maya marks a moment of liberation. The child is presented from her own viewpoint. She is painted in clashing bright colours, with clear dark outlines and a lively disregard for proportions. Safely interlocked with her toys, she stares back at the viewer with something of the disconcerting candour of the artist.

Wife Jacqueline

Jacqueline Roque was the last of the many female companions whom Picasso portrayed but he painted more images of her than of any other, producing in one year alone, more than 70. This one is important because it was done in the year Roque became his second wife. Picasso’s most audacious years as an artist were over. But as a subject she seemed to endow him with a new energy. Sometimes he painted her with a lurid Spanish palette. But this image has a delicacy and subtlety that seems to speak of his tenderness.

Rachel Campbell Johnston, Chief Art Critic

Editor's choice

• U2 at Nou Camp Stadium, Barcelona
• The 50 Best Movie Villains
• The 15 golden rules of theatre etiquette