When I was last at the Eiffel Tower, in February, the street vendors selling souvenirs and trinkets scattered when they saw police approaching. It was quite a sight. Men with enormous wire rings, each one strung with hundreds of miniature monuments, jangled as they sprinted away from the French authorities. When the police were gone, they slowly came back, offering tourists one euro versions of Gustave Eiffel's famous iron structure.

But in Paris this week, the interactions between vendors and police lost the playful habitualness of that back-and-forth.

On Sunday, scuffles broke out when police attempted to evict the businessmen. The vendors threw rocks and bottles, and according to reports, three riot police -- or Compagnies Républicaines de Sécurité officers -- were injured in the battle.

Police arrested 10 souvenir-sellers at the Eiffel Tower on the day of the clash, and police say they arrest about 50 vendors across the city on any given day, according to The Connexion, a French English-Language paper.

All street vendors will now be systematically arrested and we will not tolerate these sales, Jean-Louis Fiamenghi, a senior police official, told BBC.

The vendors are primarily immigrants, mostly from Africa but also from Eastern Europe. They sell everything from glow-in-the-dark Tour Eiffels to water bottles to key-chains. At night on the Champ de Mars -- the long lawn leading up to the monument from the east -- men walk around selling bottles of wine to tourists and Parisians who have settled down to watch the hourly light-display on the tower.

The initial confrontation Sunday began because vendors were upset when one of their comrades was injured running away from police. According to Le Parisien, a man who darted across a metro rail to escape arrest was electrocuted and needed to be hospitalized. Angered by the event, the vendors refused to run when police came to detain them.

While it is slightly annoying to be asked countless times while waiting in an hour long line if you want to buy a souvenir, vendors are not as troublesome as a rock-flinging fight among a thousand sight-seers would be. Paris, like many European cities, is full of street-vendors, and in my experience the ones under the Eiffel Tower are the least threatening of any in the city.

For these men, selling knick-knacks, which is an extremely difficult way to make a living, just became that much harder.