Swiss police have arrested two men as Geneva is on high alert after finding traces of explosives in a car. The suspects were arrested on suspicion of the manufacture, concealment and transport of explosives and toxic gases, as well as on suspicion of violating the prohibition of groups such as al Qaeda, Islamic State (Isis) and other similar organisations.

The two people were charged on Saturday 12 December, according to a statement from the Office of the Attorney General of Switzerland, with police confirming that they had found traces of explosives inside the vehicle. Both are believed to be of Syrian origin.

Geneva's public prosecutor gave no confirmation yet on the precise nature of the chemicals found in the car although a news conference is expected later.

Armed police were deployed at locations around the Swiss city, which is home to the UN's European headquarters. The Geneva region raised its alert level to three on a five-point scale on Thursday following fears of a potential terror attack.

Swiss President Simonetta Sommaruga said on Friday 11 December that a "foreign authority" had handed over intelligence information to Swiss intelligence about "a potential IS cell in the Geneva area".

Authorities have been looking for at least two people with indirect links to suspects in the November 13 Paris terrorist attacks. It was not immediately clear whether Saturday's arrests were linked to the attacks in Paris, in which 130 people were killed.

Swiss Public Television also reported that police had been tracking a Belgian van earlier in the week that is believed to have briefly entered Switzerland on Tuesday, 8 December.

A security guard at the United Nations in Geneva told Reuters on Thursday, 10 December that Swiss authorities were searching for "four guys" believed to be in the area, according to the Swiss Broadcasting Corporation. UN security guards were stationed with sub-machine guns at entry points for cars, a highly unusual measure at the building.