Marie Didieu's house at Ras Gitau on Manda Island. Photograph: Simon Maina/AFP/Getty Images

Marie Didieu, a disabled  66-year-old French woman, was kidnapped yesterday from her vacation home on Manda Island, part of the Lamu archipelago, not far from where a British tourist was killed and his wife abducted three weeks ago.  The kidnappers arrived and departed by speedboat early Saturday morning.  They were pursued by Kenyan naval craft but escaped to Somalia.

Last month, David Tebbutt was killed and his wife Judith was kidnapped from Kiwayu Safari Village, an exclusive Kenyan resort, not far from Mandu Island.  Judith Tebbutt is believed to be being held in central Somalia, by a pirate gang.   The British Foreign Office has issued a warning to British citizens to stay away from all Kenyan beaches within 93 miles (150km) of the border with Somalia.  The French government also warned its citizens against visiting Lamu.

The identity of the kidnappers is unclear. The Somali coast near the Kenyan border is believed to be controlled by the Islamist group al-Shabab.  Nevertheless, reports that Judith Tebbutt is being held by by a pirate gang in Central Somali may suggest cooperation between the two groups.