STOCKHOLM - Swedish police evacuated 273 people from a Pakistan International Airlines jet diverted to Stockholm due to a bomb alert Saturday and detained a passenger on suspicion of preparing aircraft sabotage, officials said.


However, no explosives were found on the man or on the Boeing 777, and all passengers — except the suspect — were allowed back on the plane nine hours later. It took off for Manchester, England, from where the passengers would continue their journey to Karachi, said Jan Lindqvist, a spokesman for airport operator Swedavia.


The Royal Canadian Mounted Police said it was investigating whether the incident was a "terrorism hoax."


The plane was travelling from Toronto to Karachi when the pilot asked to land after Canadian authorities received a tip that a passenger was carrying explosives.


A SWAT team detained the suspect as he was evacuated from the aircraft along with the other passengers. An AP reporter at the airport saw the passengers boarding yellow airport buses parked near the aircraft.


Police described the suspect as a Canadian citizen of Pakistani origin, aged about 30, but said they had not confirmed his identity.


A spokesman for the state-owned Pakistan International Airlines said the suspect was a 25-year-old Canadian national.


The tip was "called in by a woman in Canada," police operation leader Stefan Radman said, adding that Swedish police took the threat seriously.


Royal Canadian Mounted Police spokesman Sgt. Marc LaPorte said an anonymous caller called twice Friday saying a man on the flight had explosives.


"The first call provided vague information. It did lay out that there was an individual on that specific flight in possession of explosives and then the second call provided more details with regards to the identity of the person," LaPorte said.


He declined to elaborate on the caller, saying there was potentially a criminal offence involved.


"We take any call of this nature very seriously. Basically we have to ascertain the credibility and reliability of the call and try to determine whether there was a deliberate intent on behalf of the caller to mislead the police or if it falls into the definition of a terrorism hoax."


Police officials said the man was not on any international no-fly lists and had cleared a security check in Canada. He didn't resist when the SWAT team took him into custody.


Investigators were questioning the man at a police station, and a prosecutor was to decide whether to formally arrest him.


In Pakistan, a spokesman for state-run PIA confirmed the incident involved flight PK782 to Karachi.


"The plane has landed at the Stockholm airport due to security reasons," airline spokesman Sultan Hasan said.


The passengers were waiting at the "international holding area" at the airport as they and their luggage were scanned and searched, Hasan said. Pakistani diplomats were at the airport to co-ordinate with the security officials.

PIA said there were 255 passengers and 18 crew members on the plane. Of the passengers, 102 were Canadian nationals, 139 Pakistanis, eight U.S. citizens, three Indians and one each from Japan, Malaysia and Bangladesh.

The Canadian Embassy in Stockholm was in contact with local authorities to gather additional information, Foreign Affairs spokesman Alain Cacchione said.