Four days after the Parliament's security was breached, the Delhi Police on Sunday sped up the investigations as teams recorded the statements of family members of the accused and claimed to have recovered fragments of some broken and burnt mobile phones from Rajasthan's Nagaur.

The houses of the accused were searched and the statements of their family members were recorded by the police team, sources said.

Police have added IPC sections related to destruction of evidence to the FIR against the accused.

An officer privy to the investigations said a few pieces of mobile phones were recovered on Saturday on the instance of Lalit Jha, who was among the six arrested by the police in connection with the case.

A team of Delhi Police's Special Cell on Saturday took Jha to Rajasthan's Nagaur where he stayed with the help of accused Mahesh Kumawat, officials said.

Sources said the Delhi Police has added more IPC sections, including Section 201 (destruction of evidence/disappearance of evidence) in the FIR registered on December 13. Police have filed terrorism charges under the stringent Unlawful Activities (Prevention) Act against the accused.

Police officials said Jha and Kumawat intentionally destroyed the mobile phones to hide technical evidence related to the case.

The Delhi Police has so far arrested Sagar Sharma, Manoranjan D, Amol Shinde, Neelam Devi, Lalit Jha and Mahesh Kumawat for their alleged involvement in the Parliament security breach case.

Two men -- Sagar Sharma and Manoranjan D -- had jumped into the Lok Sabha chamber from the public gallery during Zero Hour, released yellow smoke from canisters and shouted slogans, before being overpowered by the MPs.

Around the same time, two others -- Amol Shinde and Neelam Devi -- released coloured smoke from canisters while shouting "tanashahi nahi chalegi" outside the Parliament premises.

Jha, who was present outside the gate, had recorded the act on his mobile phone. After uploading it on social media and sharing it with his friends, he went to Nagaur in Rajasthan. Kumawat and accused Kailash, who are cousins, allegedly arranged his stay there.

Later, Jha and Kumawat came to Delhi and surrendered to the police.

The sources said the role of one more suspect, who was part of the Bhagat Singh Fan Club page, has surfaced.

"Jha had sent a video to him and asked him to circulate it. He had also written 'Jai Hind' after sending the video," a source said, adding that the officials may call him for questioning soon.

During investigations, police found that the accused, Sagar and Manoranjan, had come early in the morning to get the front row in the visitors' gallery of Parliament on December 13.

The officials still suspect that the accused were handled by some other persons or handlers who brainwashed them in the name of revolutionary leader Shaheed Bhagat Singh to commit the act of breaching the Parliament security.

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