In a bid to protect its ancient glories from modern perils, Rome has banned cars and motors scooters from the boulevard that slices through the city’s ancient Roman forums toward the Colosseum.

Traffic police started enforcing the new restrictions at dawn Saturday, diverting private cars and motor scooters to side streets so they will no longer clog the famed Via dei Fori Imperiali.

Only buses, taxis, bicycles and pedestrians will be allowed on that boulevard, which was constructed in the 1930s by dictator Benito Mussolini so military parades could roll past reminders of the ancient Roman empire.

Rome’s new mayor, Ignazio Marino, says the ban will stop the Colosseum from being a traffic “roundabout” and reduce pollution.

Sidewalks have been widened so people can stroll in leisure down the boulevard.

The bizarre behaviour of a troop of ‘hysterical’ s at a Dutch zoo has been blamed on everything from an earthquake to a UFO.

Ordinarily seen scampering around on their island at the in the northern Netherlands, the gang of 112 monkeys have been sitting frozen on the ground and turning their backs on visitors this week.

The baboons have even lost their appetites, say baffled zoologists at the park, who have heard various theories as to what may be behind the animals’ strange behaviour.

‘They became panicked at the end of the day on Monday, they were hysterical, not jumping around but behaving strangely,’ zoologist Wijbren Landman told AFP.

‘On Tuesday and Wednesday they just sat in the trees or on the ground, hardly moving or eating.’

Mr Landman described various theories put forward to explain the bizarre scenes at the zoo, with some suggesting the baboons may have spotted a predator – either a real one or an image of one on a visitor’s t-shirt – or felt the rumblings of an earthquake.

The zoologist admitted he was yet to hear an explanation that ‘holds water’.

‘The craziest suggestion was that it was caused by a UFO,’ Mr Landman said.

Baboons at the zoo, who were all born in captivity, have behaved this way four times in the past 20 years, the team at Emmen Dierenpark said.

But their activity has not been observed among any baboons anywhere else, either in captivity or in the wild, according to a report in the Huffington Post.

Experts consulted by staff at Emmen Dierenpark have so far failed to shed any light on the mystery, but the animals have shown signs of returning to normal.