Delays as Rio tightens airport security

New, stricter security checks have been implemented in Brazilian airports this week, stalling travellers and delaying flights less than three weeks before Rio de Janeiro hosts the Olympics.

At 6am on Monday, long, chaotic lines formed at Congonhas regional airport in Brazil’s biggest city, Sao Paulo.

Within 30 minutes, more than 700 people were waiting on the building’s first and second floors to pass through security checkpoints. The lines eased up by the afternoon.

Smaller airports elsewhere in Sao Paulo state in southern Brazil also reported problems. There were also long lines at the Santos Dumont regional airport in Rio de Janeiro, where the Games are scheduled to open on August 5.

The new measures took effect days after the truck attack that killed 84 people in Nice, France, underscoring potential security threats at big events.

Authorities say some 85,000 soldiers and police officers will patrol Rio’s streets during the Olympics.

Because of the stricter checks in airports, Brazilian state airport administrator, Infraero, has recommended that travellers arrive two hours before scheduled domestic flights instead of 30 minutes.

The new procedures include body searches, removal of electronic items from bags before scanning and more thorough luggage inspections.

Brazil’s aviation agency said the steps are necessary.

‘‘Due to this vacation period and with the proximity of the Olympic Games, demand for air transportation will surely increase,’’ the agency said.

Brazilian authorities expect more than 500,000 foreign tourists to visit Rio for the Olympic Games.