New Delhi: Home Minister Rajnath Singh on Tuesday said he was "deeply pained" after an alleged assault on Delhi Chief Secretary Anshu Prakash during a meeting with Chief Minister Arvind Kejriwal and some AAP MLAs at Kejriwal's residence.

"I am deeply pained by the happenings involving the Chief Secretary of the Delhi Government. The civil servants should be allowed to work with dignity and without fear," Rajnath Singh tweeted.

The Union Home Ministry sought a report from Lieutenant Governor Anil Baijal on the alleged assault.

"The LG has been asked to submit his report by today evening," a Home Ministry official said.

The ruling AAP denied the allegation even as the IAS Association Secretary, Manisha Saxena, complained to Lt. Governor Anil Baijal, claiming that the attack on Monday night was a "planned criminal conspiracy" against the top bureaucrat.

Speaking to the media after the meeting with Baijal, Saxena said they have asked the Lt. Governor to take strict action against the accused MLAs. 

She also said the officers would work on Tuesday with a black band as a mark of protest and that the association has also filed a police complaint. 

She said Prakash was called for a meeting around midnight on Monday where Kejriwal along with his deputy Manish Sisodia and 10 to 12 MLAs was present.

The meeting was on "some advertisements by the Delhi government which were in violation of the Supreme Court's guidelines".

"For the past couple of years, officers have been insulted and humiliated in public. The attack on the Chief Secretary is an attempt to intimidate the bureaucracy to toe the line of the powers that be."

Saxena, however, refused to name the MLAs who attacked the Chief Secretary.

AAP and BJP spar: BJP MLA Vijender Gupta, who is also the Leader of Opposition in the Delhi Assembly, alleged that Kejriwal "in his dictatorial style" called the Chief Secretary at midnight on Monday and "berated" him in front of his MLAs. 

Gupta said Kejriwal was "drunk on power" and his concern was only about why more funds were not dispersed for advertisements. "Such is the state of affairs under AAP."

"In total, nine AAP MLAs were present at the CM's residence when the Chief Secretary was assaulted. They represent people of Delhi but are nothing short of urban naxalites. How utterly disgusting behaviour," he said. 

But Delhi government spokesperson Nagendar Sharma denied the allegation saying the Chief Secretary was making false accusations at the behest of the BJP. 

Sharma said during a meeting at Kejriwal's residence on the "faulty implementation" of Aadhaar that "deprived about 2.5 lakh families of ration", the Chief Secretary refused to answer questions saying he was not answerable to MLAs or the Chief Minister but only to the Lt. Governor. 

"He even used bad language against some MLAs and left without answering any questions.

"Moreover, it is false information that the meeting and the argument was about TV ads. The entire discussion was on how large number of families were not getting ration," Sharma said in a statement.

"Obviously, he (the Chief Secretary) is doing it at the BJP's behest. The BJP has stooped very low in disrupting governance in Delhi through the Lt. Governor and officers.

"If the Chief Secretary can make such wild allegations, one can imagine the kind of obstacles that are being created in AAP government's work by BJP through the officers."

Prakash was allegedly assaulted by AAP MLAs in a meeting at Chief Minister Arvind Kejriwal's residence, sparking protests on Tuesday and threats of a pen-down strike in government offices in the capital.