Kenyan police have fired tear gas at pupils of a big school in Nairobi who were protesting about the sale of their playground to a private developer.
The pupils had returned to the Lang'ata school after a two-week teachers strike to find the play area fenced off.
The school has about 1,000 children between the ages of three and 14 and is run by Nairobi city council.
Several children were hurt in the police action to disperse the protest and have been taken to hospital.
Some of them had confronted riot police, waving sticks at them.
At least one police officer was injured when he was struck by a stone thrown by a protester.
The demonstrators also included teachers at the school and political activists.
It was not immediately clear how the developer came to take possession of the land, which lies less than five kilometres west of the city centre.
The city council has said the playground is public land. It has not commented on the legal status of the apparent sale.
Critics have alleged that corrupt elements were behind a deal to turn the land over to the developer.