Picture power: Tear gas at Kenyan primary school

Earlier this week, scenes of schoolchildren running away from tear gas fired by police in the Kenyan capital, Nairobi, sparked condemnation and even a hashtag, #OccupyPlayGround.

Pupils at Lang'ata school were protesting at the loss of their playground. They had returned after a two-week teachers' strike to find it fenced off by a private developer. Agence France Press photographer Tony Karumba was on hand to record the demonstration and here he recalls the event.

"My experience is that land disputes even with the potential of bloodshed and worse will generally not draw such zealous responses from police. I expected there would be some drama being that Kenya's now renowned activist and journalist, Boniface Mwangi was expected at the protest.

"When the kids forced their way past a police cordon at the main entrance to their school I thought to myself that any kind of confrontation would obviously have to be played down in the children's presence.

"I was rudely shocked when the first tear-gas canister was lobbed into the midst of a group of them.

"At first I was unable to react as a photographer and I stared aghast for some seconds at screaming, terrified kids scrambling over each other on to a nearby motorway and a ditch. I raised my camera just in time to get a group of them trying to race up a foot-bridge looking back wide-eyed at a cloud of tear gas.

"At that moment, I had no major concern for my safety, as it's a situation I've been through countless times before. The real challenge here to my profession was to watch hapless, shell-shocked kids, the older ones suddenly angry at what I imagine was the betrayal by the officers who, their elementary schooling has taught them, are there to protect them."

The story does not end there though as the BBC's Ed Thomas reports.

Here are some more of Tony Karumba's pictures from the day.