Here are the 10 latest developments in this story:
Denying any wrongdoing, AAP's Amanatullah Khan, who had been in trouble with the law in the past, surrendered at the police station this morning and was formally arrested. Lawmaker Prakash Jarwal was arrested late last night. A court has rejected the police appeal to get their custody for questioning.
AAP's Sanjay Singh said the party was being "hounded". "Everyone questions only the AAP. Chief Secretary says he was beaten. There is no proof. Is his the ultimate word? What about the word of a minister?" he said at a press conference today after Mr Khan's surrender.
The report of the medical examination of the Chief Secretary showed he sustained injuries on his forehead and cuts on his face, sources said. There was also swelling behind the ears.
Though bureaucrats are not officially on strike, they have said they will not attend any meeting outside office hours and premises and would only correspond through files -- a move that's expected to slow down work. Officials from IAS and DANICS cadre have sought an appointment with President Ram Nath Kovind.
The Delhi High Court has refused to intervene following a petition on the issue. The court said "They (police) will take action in accordance with law. We will wait for the final outcome".
In his complaint to the police, Anshu Prakash alleged that the midnight meeting was called to force him to clear release of TV ads on three years of the AAP government. The assault was "pre-meditated and in conspiracy of all present", he said, which means the Chief Minister, his deputy Manish Sisodia and nine other lawmakers could also face criminal action.
AAP has accused the Chief Secretary of lying, citing video footage of him leaving the Chief Minister's home that night. The party also said its minister Imran Hussain and his personal secretary were beaten up at the Delhi Delhi Secretariat on Tuesday by a mob that was incited by the BJP, but the police have done nothing about it.
Delhi Lieutenant Governor Anil Baijal has sent a report on the matter to the home ministry. Union Home Minister Rajnath Singh has said civil servants "should be allowed to work with dignity and without fear". AAP said it is unfair that the Minister had not heard their version before making the statement.
The BJP and Congress have been sharply critical of Mr Kejriwal and his lawmakers. Delhi BJP's Manoj Tiwari called the AAP lawmakers "goons" and the assault an "act of urban naxalism". Ajay Maken, the Delhi Congress chief, asked the Chief Minister to apologise.
The relation between AAP and Delhi bureaucrats has been strained since the party came to power in 2015. The Delhi government has no control over important departments like law and order, land and police. AAP accuses the Lieutenant Governor and bureaucrats of obstructing it on the orders of the BJP-led central government.
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