The CBI on Thursday visited the Directorate of Information and Publicity (DIP) of the Delhi government and collected documents relating to the Aam Aadmi Party (AAP) government's "Talk to AK" media campaign.

The CBI on Thursday visited the Directorate of Information and Publicity (DIP) of the Delhi government and collected documents relating to the Aam Aadmi Party (AAP) government's "Talk to AK" media campaign.

The Central Bureau of Investigation's (CBI) move came a day after it filed a preliminary inquiry against Delhi's Deputy Chief Minister Manish Sisodia and some unnamed state government officials to probe alleged irregularities in the campaign. 

"Our team visited the DIP office in Delhi Secretariat to collect some documents to probe the allegation of improprieties and violation of extent rules and regulations in award of work pertaining to the Delhi government's media campaign 'Talk to AK'," a CBI official told .

It was not a raid or search, he added.

Earlier in the day, Delhi Chief Minister Arvind Kejriwal attacked the premier investigating agency, saying it is scared of the Deputy Chief Minister.

"Today (Thursday) Manish (Sisodia) kept waiting for the CBI, but it did not turn up. Till now people used to fear CBI, but it is for the first time when CBI is fearing someone," Kejriwal tweeted.

The CBI official, however, said that the agency never makes raids in case of a preliminary inquiry.

The 'Talk To AK' campaign was an interactive session of the Delhi Chief Minister, through which people could reach out to the AAP leader through social media.