Singh said he agreed with Mamata's contention that Delhi was not a safe place and attacked the Congress-led UPA government over the situation in the national capital which he said was "slipping into a state of anarchy with each passing day".
"Whatever has happened with Mamataji and (West Bengal Finance Minister) Amit Mitra, I condemn it strongly. In clean politics, it is expected that if any political party or organisation wants to lodge its protest on an issue, there is a way to do so. But if anyone tries to lodge its protest by taking to violence, I feel the government should take stern steps against them," Singh said.
The BJP chief said "Delhi is slipping into a state of anarchy every passing day. When Chief Ministers and Finance Ministers are not safe in Delhi, then one can imagine how will the common man remain safe. I demand that there should be a proper investigation and action on this issue."
Singh alleged the situation in Delhi is such under the Congress-led UPA government that even Chief Ministers and Finance Ministers don't feel safe.
BJP leaders have been trying to reach out to the TMC Chief in a bid to win her over ahead of next general elections.
Gujarat Chief Minister Narendra Modi had yesterday commended Mamata government.