Christophe Chamley, 70, a professor at Boston University, will likely be fined thousands of dollars for a search operation

An economics professor who sparked a massive manhunt when he failed to return from a mountain hike is now facing a bill of thousands of dollars for wasting rescuers' time.

Christophe Chamley, 70, who works at Boston University, planned a solo hike over two mountains in New Hampshire last month but changed his pre-agreed plans last-minute.

Instead of returning home after conquering both peaks Mr Chamley stayed overnight at a luxury hotel, but a 1am WhatsApp message to his wife telling her he was fined failed to send.

When he failed to return home she called mountain rescue to report him missing, sparking a huge search operation.

In total the search involved 25 people, snow cat automobiles, a National Guard helicopter, and dozens of pieces of specialist cold weather equipment.

Adding urgency to the search, Mr Chamley's wife also informed rescue crews that he had a medical condition.

It is not yet clear why Chamley went to the hotel instead of heading back home.

Mr Chamley had set off across Mount Adams and Mount Jefferson, in the White Mountain National Forest, around 7.45am on Sunday April 22.

25 rescuers using snow cat automobiles and a National Guard helicopter searched for Mr Chamley after he went to a hotel instead of going home, but failed to inform his wife

He managed to summit both mountains, Fish and Game Lt. Wayne Saunders told the Concord Monitor, but then 'decided to bail off' and headed for the Omni Mount Washington Resort hotel instead.

He checked in around 1am which is when he sent the message to his wife, but failed to check if she received it, Saunders said.

Around 3.45am she called the emergency services to report him missing, and a rescue mission was launched.

Several hours into the rescue operation staff at the hotel informed search crews that he had checked in during the early hours of the morning.

Chamley did not wake up until 11am, and was completely unaware of the operation until it was over.

Mr Chamley has now been informed he will likely be billed for the operation, according to the New Hampshire Union Leader.

Col. Kevin Jordan, chief of the New Hampshire Fish and Game Department, said the final amount is still to be approved, but will likely run into the thousands of dollars.

A 2008 law allows the state to bill anyone whose negligent actions led to a search being launched.

For $25 people can purchase insurance cards exempting them from charges, but Mr Chamely did not have one.

After several hours of looking, Mr Chamley was eventually traced to the Omni Mount Washington Resort where he had stayed the night

Speaking to the Union Leader, he said: 'Everybody at Fish and Game had a superb, extraordinary, and professional care.

'They were, of course, a little upset, but after that they were very caring.'

The largest fine ever issued under the law was a $25,000 bill handed to teenager Scott Mason in 2009 for a three-day mountain search.

Mason, an Eagle Scout, had planned to spent one day hiking a trail but sprained his ankle and became lost when he tried to take a shortcut.

He was praised for using his survival skills to identify suitable sleeping spots and build fires, but state officials argued he was under-prepared for the conditions.

Mason and his family eventually settled for a lesser amount that was not disclosed.