VIENNA/AMSTERDAM (Reuters) - Dutch Prince Johan Friso was in critical but stable condition in an Innsbruck hospital's intensive care unit Friday after an avalanche buried him while he was skiing off trail in the Austrian alps, police said.

The Austria Press Agency said the 43-year-old prince, middle son of Queen Beatrix, was in Innsbruck's University clinic.

"After the emergency call, rescue crews were on the scene with rescue helicopters. He could be located immediately and freed," a police official in the western ski resort of Lech told Reuters. The prince had been skiing with a group, he said.

The Dutch royal family often spends winter holidays in Lech in the western province of Vorarlberg - which like other parts of Austria has been blanketed with heavy snow in recent weeks.

Many parts of the country have avalanche alerts in effect.

Prince Johan Friso's older brother is Crown Prince Willem-Alexander and his younger brother is Prince Constantijn.

Johan Friso is not an heir to the throne because he married scandal-touched Mabel Wisse Smit without the government's permission in 2004. He would otherwise have been second in line ahead of his younger brother.