BBC News website reader Louise Hemmings was in Place de la Republique in Paris, where fights and running battles took place between police and protesters opposed to France's new youth labour law.
Police and protesters clashed repeatedly in the square
Ms Hemmings, a 19-year-old British student in Paris, sent updates from the protests by phone.
RUE RENEE BOULANGER, PARIS, TUESDAY, 1930 GMT
We have left the square now and I am in my friend's house nearby.
The police cleared a large part of the square and had contained a group of people who seem to have been making the most trouble into a corner of the square.
After the tear gas was fired and the water cannons were repeatedly used it all became very intimidating, so we decided to leave.
Police used water cannons to disperse the crowd
I still have a horrible taste in my mouth from the tear gas.
It had also come to the stage where I realised the only people that were there were looking to cause trouble.
The entire area had such a tense atmosphere and at times I feared for my own safety. It was quite scary.
It's really worrying that some people can turn what was meant to be a peaceful protest into an excuse to use violence against the police.
It ruins the whole point of what the protests were about in the first place.
Tear gas was also used by police
It will also definitely make the government less sympathetic to the students' cause.
I have friends here who will be affected by this law and these protests are an important way of making their voices heard.
But it makes it so much more difficult for them when they are taken over by people who are just out to cause trouble.
PLACE DE LA REPUBLIQUE, PARIS, TUESDAY, 1830 GMT
There are police absolutely everywhere now. It looks like they are trying to pen us in.
We may end up being stuck here for quite a long time.
There is a horrible smell and taste in the air after the police fired off tear gas.
There are fights breaking out all over the square between protesters and police
Some people have been badly affected by it. I saw one man getting sick due to the effects of the tear gas.
I can see three vehicles with water cannons firing into the crowd.
But it doesn't seem to be having the effect they would like as people are running towards it and shouting and whistling.
People are still throwing missiles at police also.
Some have been throwing glass and others have firecrackers that they are hurling at the many lines of riot police.
PLACE DE LA REPUBLIQUE, PARIS, TUESDAY, 1715 GMT
I am standing right in the middle of the square, in Place de la Republique, where there are thousands of people.
It is very chaotic here and it's really pretty scary and intimidating.
A number of arrests were made throughout the day
There are fights breaking out all over the square between protesters and police.
There are riot police everywhere and they are dragging people out of the crowd constantly.
People are throwing missiles at police - mainly sticks and paint bombs.
Some protesters have climbed up the monument in the middle of the square.
There are about 100 people sitting down now and they are telling others to do the same.
The protesters are mainly made up of young people, mostly students, and some middle-aged people. Some of them are pretty scary and rough-looking and some are drinking.
There are journalists and photographers everywhere as well, and a lot of the anger seems to be directed as much at them as it is at the police.
It looks like this is going to go on all evening.