The operation, which caught Ramdev and his supporters unaware, began after 1 am and it was almost over within couple of hours.
"It was a political decision. Otherwise we would not have carried out the operation although we had given permission only to hold Yaga camp and not an agitation," said the police official.
He said police tried to pursued Ramdev to leave the place peacefully but he did not heed to the request and instead asked his supporters not to leave the venue.
The official said followers of Ramdev had pelted stones at police personnel.
"We requested him to leave the place peacefully. But he did not listen to us. Then his supporters started pelting stones at us," said the official.
Earlier, police had blocked all the roads leading to Ramlila Maidan.