Singh said this hours after Modi tweeted about BJP's impressive performance in Madhya Pradesh municipal elections, in which the saffron party won eight out of ten civic bodies.
"He (Modi) was prompt and quick on tweeting over the MP civic polls. He should break his silence and tweet over Vyapam scam, Sushma Swaraj, Pankaja Munde involved in wrongdoings," Singh told reporters here.
Modi had tweeted, "MP civic poll results are gladdening. I thank people of MP for reposing their trust in BJP. I salute efforts of Karyakartas & party leaders."
During his UAE visit that commenced today, Modi is scheduled to kick start his first public engagement with a visit to Shaikh Zayed Grand Mosque, the third largest mosque in the world after the ones in Mecca and Madina in Saudi Arabia.
"I am delighted that a person who did not wish to wear a skull cap, is visiting a mosque in UAE. It is a good sign," Singh said.
In 2011, when Modi was the Chief Minister of Gujarat, he had refused to put on a skull cap offered by a Muslim cleric during his sadbhavana (harmony) fast in Ahmedabad, which had triggered a controversy. His detractors had latched onto the issue to attack him.
